dhr. prof. dr. W.J. (Wybren Jan) Buma
Faculteit der Natuurwetenschappen, Wiskunde en Informatica
Science Park A
Science Park 904 Amsterdam
1090 GD Amsterdam
Have a look at the Latest news ... and more page to keep up to date with the most recent developments and highlights of our research
Molecules and Light
... is the leading theme of our research. We use light to study the structure of molecules and to understand how structure and function are related. To reach this goal we employ several strategies. Starting from isolated molecules in the gas phase that we study with high-resolution molecular beam (single and double resonance) techniques based on fluorescence and multiphoton ionization, we answer questions as to how the conformational landscape looks like in ground and electronically excited states and how changes in electronic charge distribution induce changes in structure and functionality. We then study the effects of a medium by microsolvation where we dress molecules in a molecular beam with a controlled number of solvent molecules, and look how the properties of the individual molecules are affected, ultimately relating these results to molecular properties under low-resolution solution conditions. We complement these experiments with quantum chemical calculations that not only provide us with a solid basis for their interpretation but also suggest new experiments and ways to optimize functional properties. One of the great challenges in the field - and one that we have met successfully - is to extend the complexity of molecules that can be studied in this way from merely model chromophores to genuinely prototypical systems in molecular photobiology or for applications within, for example, molecular nanotechnology.
Structure, and thereby function, is not a static molecular property; it is a property that can be influenced by external stimuli (photons, electrons, etc.), and under non-isolated conditions it is constantly subject to external interactions. We develop and apply new methods based on light to observe structure on time scales ranging from femtoseconds to seconds, ultimately aiming to control the directionality of structure changes through manipulation of intra- and intermolecular interactions in functional materials.
We thus use the interaction between light and molecules to understand , design , and control molecular systems, and seek to cover the complete trajectory from conception of new molecular systems to their application in functional materials. Our research can therefore certainly not be associated exclusively with one of the traditional areas within chemistry or physics, but supersedes their boundaries. Scientific areas that we work in concern:
- vibronic coupling
- electron and proton transfer reactions
- polymer electronics
- photoactive proteins
- supramolecular assemblies
- functionalized photoactive surfaces
- pharmaceutical applications
Publications in refereed journals
Een meer populaire beschrijving van het onderzoek dat bij Molecular Photonics wordt gedaan wordt gegeven in een van de 'Onderzoek uitgelicht' afleveringen.
A more popular description of the research in Molecular Photonics can be found in one of the 'Focus on Research' issues.
We regularly have vacancies on new projects. Have a look at the Vacancies page, and make your choice!
A.MSc and PhD projects
We are always interested in enthusiastic MSc en PhD students. For MSc students we regularly have projects that can be filled in on an ad hoc basis. The subjects of these projects reflect the broad scientific area in which Molecular Photonics is working: from more synthetically-oriented projects to high-resolution spectroscopy and advanced femtosecond laser spectroscopic techniques. At the same time, such projects can be rather fundamental in nature but we also have projects that are much more application oriented such as projects that we carry out together with medical centers such as the AMC and the LUMC.
For PhD students we do not have at the moment any position open. However, if you have the possibility to acquire your own funds to finance your PhD research we are always interested to get into contact with you and see how we can work together.
August 2016: Article in Nature Communications on 'molecular graphene'
The interaction of delocalized pi-electrons with molecular vibrations is key to charge transport processes in pi-conjugated organic materials based on aromatic monomers. Yet the role that specific aromatic motifs play on charge transfer is poorly understood. In our article "Electron-flux infrared response of varying pi-bond topology in charged aromatic monomers" published in Nature Communications 7, 12633 (2016) we show that the molecular edge topology in charged catacondensed aromatic hydrocarbons are responsible for spectacular differences in transport properties, allowing for smarter design of new materials. Great work showing off the tremendous (and unique) benefits of the Free Electron Laser facility FELIX !
January 2016: Article in the Astrophysical Journal on the complex fingerprints of Polycyclic Aromatic Hydrocarbons (PAHs)
High-resolution laser spectroscopy for astronomy ! Molecular spectroscopy has been at the basis of the identification of PAHs in the interstellar medium. Their spectroscopic signatures are nowadays used as sensitive probes for the physical and chemical conditions in various astrophysical environments and for the evolution of cosmic carbon. In our article "High-resolution IR absorption spectroscopy of polycyclic aromatic hydrocarbons: the realm of anharmonicity" in Astrophys. J. 814, 23 (2015) we report high-resolution studies that show that these fingerprints are far more complex than assumed so far and that models employed so far to analyse astronomical data are inadequate. Our results have led to quite some shock waves in the astronomical community ...
Oktober 2015: Concepts Article in ChemPhysChem
Our work on amplifying VCD signals by manipulating the "electronics" of chiral molecules and using this amplification for zooming in on their spatial structure has attracted quite a lot of interest. As a results, the Editors of ChemPhysChem have asked us to write a Concepts Article on this subject that has appeared as ChemPhysChem 16, 3363 (2015). Everything you wanted to know about boosting your VCD signals but were afraid to ask is here! Great cover picture as well! If you look carefully, you will see where the work has been done ...
September 2015: Computational Sciences for Energy Research (CSER) (Shell-NWO/FOM) grant for renewable fuels
We have been successful again in this competitive program! Together with Luuk Visscher and Roberta Croce (VU University Amsterdam) we obtained a grant for the project Renewable fuels by tuning nature. In this project we aim is to go beyond idealized models as was done before and study fully atomistic models of real biological systems. This will provide the insight needed to propose modifications that can lead to improved biofuels production. The theoretical work focuses on extending the subsystem DFT approaches developed in the Visscher group and is complemented by synthetic and spectroscopic work carried out in the groups of Roberta Croce (Biophysics of Photosynthesis, VU) and the Molecular Photonics group. Theory together with experiment: unbeatable!
May 2015: VIDI grant for Annemieke Petrignani
Molecular Photonics goes astronomical ! Annemieke Petrignani, with whom we collaborate now for some years in the context of the Dutch Astrochemical Network, has acquired a VIDI grant on the proposal "Shapes and sizes of extraterrestrial organic molecules". This project will be performed in close collaboration with the FELIX laboratory at the Radboud University and our group at the University of Amsterdam. For the course of the Vidi project her research group will be embedded in the Molecular Photonics group.Have a look at the openings she has on the Vacancies page.
January 2015: Article in Nature Communications on azobenzene
Azobenzene can be considered as one of the most prominent examples of photoactive compounds that have found their way into many light-driven technological applications. Despite its extensive use, the fundamental photodynamical processes ocurring after excitation of azobenzene are still subject of vigorous debates. In our article " Fast photodynamics of azobenzene probed by scanning excited state potential energy surfaces using slow spectroscopy" published in Nature Communications 6, 5860 (2015) we take a different approach than the ones in the time domain that have predominantly been followed in the last decades. Instead, we show that frequency-resolved studies with nanosecond lasers are able to (a) settle the debate on which pathway is followed during isomerisation and (b) obtain "high-resolution" spectra of states that live a mere 170 fs. This is quite exciting as it is clear that the same methodology has great potential for many other photoactive compounds that so far have been considered as inaccessible to high-resolution spectrosocopy. And, we finally succeeded in luring Francesco Zerbetto, with whom we have been working for a long time on various molecular spectroscopic challenges, back into fundamental molecular spectroscopy !
November 2014: Grant from NWO Fund New Chemical Innovations (NWO-NCI)
Together with the Theoretical Chemistry group of Prof. Luuk Visscher at the VU University Amsterdam and the companies Scientific Computing & Modelling N.V. (The Netherlands) and BioTools, Inc. (USA) we have received a substantial grant for the development of a user-friendly analytical tool for determining the absolute configuration of chiral molecules using Vibrational Circular Dichroism. In this project spectroscopic methods will be integrated with theoretical modelling of molecules.The public-private partnership with the companies involved is aimed to make the tool accessible for application in industry. We are very pleased that we will be working together on this project with Prof. Larry Nafie, one of the pioneers in the field and Chief Technological Officer of BioTools, Inc.!
October 2014: Computational Sciences for Energy Research (CSER) (Shell-NWO/FOM) grant for solar energy conversion
In a nice collaboration with Koop Lammertsma and Matthias Bickelhaupt (VU University Amsterdam) we obtained a grant for the project Solar Energy Conversion – Breaking the 700 nm Absorption Barrier. In this project we will develop novel molecular systems with optimal characteristics to absorb the 700-1000 nm region of the solar spectrum and convert it to energy. The design of these systems will in first instance be done using a theoretical approach, but importantly, we will also benchmark these calculations with advanced spectroscopic studies.This collaborative effort once more illustrates the added value of a concerted theoretical and experimental approach.
The article on sunscreens has caught the attention of high-impact journals! Nature Chemistry has dedicated a News and Views article on it. Apart from the attention this particular work receives, it is very nice that the article recognizes and emphasizes the role of fundamental science in technological applications.
July 2014: Article in The Journal of Physical Chemistry Letters on sunscreens
Our article " Excited state dynamics of isolated and microsolvated cinnamate-based UV-B sunscreens" has been published in J. Phys. Chem. Letters 5, 2464-2468 (2014). We show that in this commonly used class of UV-B filtering agents electronic energy is dissipated at a much slower rate than assumed so far. The presence of such a bottleneck provides an elegant explanation for reported adverse effects. At the same time, we find that one can remove this bottleneck by putting the agent into a watery environment. The work once more shows how very fundamental spectroscopy can have major contributions to an area that generally is not associated with molecular beam spectroscopy. As you can see below, this is a subject that attracts a lot of attention!
March 2014: Article in the Journal of the American Chemical Society on boosting the difference between left and right
In our article "Amplified vibrational circular dichroism as a probe of local biomolecular strucure" we show that one can use auxiliary electronic manifolds (in the present case provided by CoII ions) to enhance vibrational circular dichroism signal intensities. We find that amplification factors of more than two orders of magnitude can be obtained, bringing vibrational differential absorption on an equal footing with electronic differential absorption. Our approach gives us much faster access to the stereochemistry of chiral molecular systems, but also opens up new venues to probe on a very local scale the spatial structure of large systems such as metalloproteins. By the way, nice example of added value of in-house collaborations, in this case between the Molecular Photonics and Homogeneous Catalysis groups ! And, of course, also the collaboration with Larry Nafie is one that we appreciate very much !
October 2013: Article in Phys. Rev. Letters on the critical Landau velocity in helium nanodroplets
Superfluidity is one of the most well-known properties of liquid helium below the so-called critical temperature. But does this still hold for helium nanaodroplets, a medium of increasing interest both from a fundamental as well as applied point of view? In this study in which the experimental expertise of the group of Marcel Drabbels at the EPFL and our own group is combined with the theoretical expertise of the group of Manuel Barranco of the Universitat de Barcelona we have determined for the first time that there also exists a critical Landau velocity at the nano scale. The results have been published in Phys. Rev. Letters 111, 153002 (2013). Check out on YouTube some spectacular simulations of the experiments that have been done!
November 2013: Article in Nature Chemistry on lubricating molecular machines
Our article "Water lubricates hydrogen-bonded molecular machines" has been published in Nature Chemistry 5, 929-934 (2013). We have investigated in this study how one can actively control the mechanics of molecular machines. In this case we look at one particular architecture (rotaxanes) and show that we can influence the rate with which the components of the machine move with respect to each other.
May 2013: ECHO grant for boosting the difference between left and right
Despite decreasing budgets and an increasing number of applications, Molecular Photonics remains successful in acquiring funds to perform high-level research. VCD is one of the most powerful probes of molecular stereochemistry and structure but suffers heavily from the "Law of conservation of misery" as the information content is much richer than with other methods but at the same time much more difficult to obtain. In the 2012-2013 round of the NWO-CW ECHO program Buma and Woutersen received an ECHO grant for the development and application of novel methods to measure Vibrational Circular Dichroism (see also Vacancies page). As a personal note I can add that my wife (Roberta Bursi, one of the PhD students of one of the godfathers of VCD, the late Philip J. Stephens) thus finally got her way to let me work on VCD as well ...
February 2013: Bryan E. Kohler distinguished lectureship University of California, Riverside
In Februari 2013 I have been bestowed the immense honor of being awarded the lectureship established in honor of Bryan E. Kohler, one of the giants in the field of molecular spectroscopy who has made a huge impact in the field of the spectroscopy of polyenes. I feel very humble and flattered when looking at the extensive list of previous holders of this lectureship.
September 2012: NWO Graduate Programme for HRSMC
As a result of being selected in a competitive program for Graduate Schools, the HRSMC has received in September 2012 funding (800 kEuro) from the Dutch Research Council (NWO) to offer young top talents the possibility to participate in the programme "Sustainability: the molecular approach". In the final stage of the Master Programme, students are challenged to develop their own ideas within the framework of the programme into a PhD research proposal.
April 2012: NWO BAZIS grant for Spectroscopic Research at LaserLab Amsterdam
Together with the Physical Chemistry group of Prof. M.H.M. Janssen (Free Univerty Amsterdam) the Molecular Photonics group has received a substantial equipment grant for the proposal "Photons for Chemistry". BAZIS grants are grants for research groups that have been recognized as belonging to research priority areas in the Physics and Chemistry sector plans. The grant enables us to update and extend our laser infrastructure that is at the basis of our understanding of the interaction between light and matter. In particular, it allows us to go full speed ahead on our program to translate this understanding into innovative molecular systems and materials with user-defined properties. Moreover, since the equipment is part of LaserLab Amsterdam also external users will have significant advantages from this extensive overhaul of equipment. We hope to see you make use of it soon!
October 2011: publication in Chemical Communication on boosting up Vibrational Circular Dichroism signals
For some time now we are using Vibrational Circular Dichroism (VCD) to study molecular stereochemistry and conformational structure. VCD is very powerful tool but generally suffers from small signal intensities that impede application of the technique as a standard analytical tool. Strategies to enhance VCD signals are therefore of substantial importance. In this Communication we show that we can obtain an order of magnitude enhancement by carefully modulating the electronically excited-state manifold. The article has received quite some attention, not in the least because it was given ample publicity on the back cover of the issue of Chemical Communications in which it appeared!
September 2011: Opening symposium Institute Quantivision
September 21 marked the official opening of Institute Quantivision, a collaboration between the VUmc, AMC,NKI/AVL, VU, UvA and companies to develop medical imaging devices, software and protocols to enhance the efficiency, efficacy and economy of healthcare. Prof. dr Wybren Jan Buma is one of the members of the Management Team. This Institute has originated from a ZONmw initiative, called Innovative Medical Devices Initiative to establish regional Centres of Research Excellence, where healthcare, business and science collaborate on the development of new medical devices that enable future health care at high standards, in an aging population with decreasing numbers of working forces. We are very excited to be part of this Institute and are looking forward to bring in our Molecular Photonics expertise.
July and September 2011: Molecular Photonics for Health
One of the more applied areas the Molecular Photonics group has started to work in, is the area of Medical Photonics. Presently, we have a large portfolio of joint projects with various University Medical Centers that started with the, by now long-standing, fruitful collaboration with the Biomedical Engineering and Physics group at the Amsterdam Medical Center (AMC). Two typical examples are included here; one which concerns a study on new methods for age determination of blood stains that was published in PLos ONE, and one which focuses on the development of new upconversion nanoparticles for applications like photodynamic therapy that was published in the Journal of Physical Chemistry Letters
May 2011: ECHO grants for molecular machines in the gas phase
The Molecular Photonics group has been very succesful in the 2010-2011 ECHO round of the Netherlands Organisation for Scientific Research (NWO). Both Sander Woutersen and Wybren Jan Buma were awarded ECHO grants for research on molecular machines. ECHO grants are €260,000 project grants designated for Excellent CHemical Research projects . ECHO grants are designed to facilitate high-quality research projects rooted in intellectual curiosity. This will allow for the development of audacious ideas, and help lay the groundwork for the research themes of the future and/or scientific innovation.
December 2010: Article in Nature Nanotechnology on photoluminescence from silicon nanocrystals
In a very nice and fruitful collaboration with the groupof Tom Gregorkiewicz (WZI, UvA) silicon nanocrystals have been studied. The resulting article " Red spectral shift and enhanced quantum efficiency in phonon-free photoluminescence from silicon nanocrystals " has been published in Nature Nanotechnology 5 , 878-884 (2010). The article has been highlighted in the News and Views section of the issue.
September 2010: Article in the Journal of the American Chemical Society on the development of a novel method to obtain IR spectra of molecular ions with ultra-sensitive detection
The continuing collaboration with the group of Dr. Marcel Drabbels at the EPFL has led to an article entitled " IR spectroscopy of molecular ions by nonthermal ion ejection from helium nanodroplets " which has been published in the Journal of the American Chemical Society 132 , 14086-14091 (2010) as a regular article. We report experiments that have enabled the detection of IR absorption in cold molecular ions with a sensitivity that is at least two orders of magnitude better than what was possible up till now. The experiments are the first of its kind in which helium nanodroplets are applied to obtain vibrational spectra of molecular ions.The results hold great promise for the future as was recognized by Chemistry World which highlighted this publication!
June 2010: Article in Science on the operation mechanism of molecular machines
Our article " Operation Mechanism of a Molecular Machine Revealed Using Time-Resolved Vibrational Spectroscopy " has been published in Science 328 , 1255-1258 (2010). In this article we look at the mechanical behavior of molecular-level machines using vibrational transitions as probes for determining how the parts of the machines move with respect to each other. More detailed information can be found in the link indicated below
May 2010: Article in Angewandt Chemie on releasing a molecular brake
Our Communication " Controlled hydrogen-bond breaking ina rotaxane by discrete solvation " has been published in Angewandte Chemie Int. Ed. 49 , 3896-3900 (2010). It has been selected as one of the highlights with an artful frontispiece made by one of the authors, Dr. Nadja Saendig. This article, in which we show how to release the macrocycle from the thread by solvating a rotaxane with one solvent molecule at a time, has attracted quite some attention. Look at the YouTube link to see a movie of what is happening!
April 2010: Communication in Journal of the American Chemical Society on unveiling the spectroscopic properties of para-coumaric acid
In our Communication " High-resolution excitation and absoption spectroscopy of gas-phase p-coumaric acid: unveiling an elusive chromophore " in the Journal of the American Chemical Society 132 , 6315-6317 (2010) we report on high-resolution spectroscopic studies of isolated para-coumaric acid (pCA). Since this molecule is the chromophore of the Photoactice Yellow Protein (PYP), many studies have - unsuccessfully - pursued the characterization of its electronically excited-state manifold under isolated-molecule conditions. Using a multicolor resonance-enhanced multiphoton ionization approach under molecular beam and helium nanodroplet conditions, we show how pCA has become accessible to high-resolution studies of its conformational and electronically excited states dynamics. Another nice aspect is the participation of two undergraduate students. Good publicity for Chemistry indeed!
August 2009: Communication in Journal of the American Chemical Society on nanomachine components in helium nanodroplets
A new collaboration has been set up with Dr.Marcel Drabbels (EPFL) in the field of helium nanodroplet spectroscopy. The Communication " Conformational flexibilityof a rotaxane thread probed by electronic spectroscopy in helium nanodroplets " in the Journal of the American Chemical Society 131 , 12902-12910 (2009) reports our first successful studies in this field. We show how dissolving single rotaxane threads into a helium nanodroplet enables us to resolve the broad absorption spectrum observed under molecular beam conditions into the separate contributions of individual conformers populated under the employed experimental conditions. This is a big step forwards as it allows us to study the properties of each single conformer instead of a property averaged over many conformers.
February 2009: Communication in Journal of the American Chemical Society on IR spectrosocopy on isolated rotaxanes
Our Communication " Stiff, and sticky in the right places: binding interactions in isolated mechanically interlocked molecules probed by mid-infraredspectroscopy " has been published in the Journal of the American Chemical Society 131 , 2428-2429 (2009). In a very nice collaboration with FOM Rijnhuizen which gave us access to the unrivaled IR laser radiation possibilities that FELIX offers, we show how we have brought multi-component systems - and with that many other molecular systems that many previously thought to be out of the question - within reach of high-resolution IR spectroscopic techniques.
January 2009: Article in Proceedings of the National Academy of Sciences on the molecular analog of Young's double slit experiment
Together with Robert W. Field (MIT) we have investigated the famous case of InterSystem Crossing (ISC) in acetylene. Employing an experimentally challenging approach based on 2D excited-state photoelectron spectrocopy, we have been able to determine the composition of coupled singlet and triplet wavefunctions. Remarkably, we find interferences between singlet-triplet coupling pathways. This observation opens up exciting possibilities for external control schemes over nonradiative decay pathways. The results have been published as " Interference in acetylene intersystem crossing acts as the molecular analog of Young's double slit experiment " in the Proceedings of the National Academy of Sciences of the United States of America 106 , 2510-2514 (2009).
28 October 2008: Experiment NL
EXPERIMENT NL (NWO research projects for the general public) is the third book in the series " Science in The Netherlands ". In 14 chapters more than 100 remarkable research projects are presented as the best that Science in The Netherlands offers.In Carpet of Nanomachines our work on rotaxanes is discussed.
July 2008: Article in Angewandte Chemie on "Proton transfer with a twist"
In a fruitful collaboration with synthetic, physical-organic, and molecular spectroscopy groups we have shown that photoinduced proton transfer in 7-(2'-pyridyl)-indole is accompanied by mutual twisting of the pyridyl and indole moieties. The results suggest that this phenomenon is quite general for several classes of organic molecules with intramolecular hydrogen bonds. The results have been published as the communication" Protontransfer with a twist? Femtosecond dynamics of 7-(2-pyridyl)indole in condensed phase and in supersonic jets " in Angewandte Chemie Int. Ed. 47 (32),6037-6040 (2008).
April 2008: Article in Angewandte Chemie on 'molding' a molecule
Our Communication " Shaping of a conformationally flexible molecular structure for spectroscopy " has been published in Angewandte Chemie Int. Ed. 47(17) , 3174-3179 (2008). It has been selected as one of the highlights, and been published with a very nice frontispiece made by one of the authors, Dr. Anouk Rijs. For highlights of this paper, see for example " Moleculaire mal dwingt grote moleculen in vorm " by Margriet van der Heijden in NRC Handelsblad,April 12, 2008, and the links given below.
March 2008: Descartes Prize
March 12, 2008 we received in Brussels the Descartes Prize for Transnational Collaborative Research as member of the SynNanoMotor consortium for" developing the first functional examples of synthetic motors on a molecular scale and many other useful and innovative nanomachines ". This has generated a lot of positive publicity, a few examples of which are given below.
February 2008: Study group Spectroscopy and Theory of NWO-CW
At the annual meeting of the Study group Spectroscopy and Theory of NWO-CW (Netherlands Organization for Scientific Research- Chemical Sciences) Prof. Silvia Volker has retired as chairwoman of the Board, and has been succeeded by Prof.Wybren Jan Buma
January 2008: Holland Research School of Molecular Chemistry
As of January 1, 2008 Prof. Kees Elsevier has resigned as Scientific Director of the Holland Research School of Molecular Chemistry (HRSMC), and Prof. Wybren Jan Buma has been appointed as his successor. Kees has done a wonderful job last years and has guided us through the reaccreditation. I'll do my best to live up to his performance!
- Maltseva, E., Amirjalayer, S., & Buma, W. J. (2017). Vibrationally-resolved spectroscopic studies of electronically excited states of 1,8-naphthalic anhydride and 1,8-naphthalimide: a delicate interplay between one pi pi* and two n pi* states. Physical Chemistry Chemical Physics, 19(8), 5861-5869. DOI: 10.1039/c6cp08735c [details]
- Patty, C. H. L., Visser, L. J. J., Ariese, F., Buma, W. J., Sparks, W. B., van Spanning, R. J. M., ... Snik, F. (2017). Circular spectropolarimetric sensing of chiral photosystems in decaying leaves. Journal of Quantitative Spectroscopy & Radiative Transfer, 189, 303-311. DOI: 10.1016/j.jqsrt.2016.12.023 [details]
- Amirjalayer, S., Cnossen, A., Browne, W. R., Feringa, B. L., Buma, W. J., & Woutersen, S. (2016). Direct Observation of a Dark State in the Photocycle of a Light-Driven Molecular Motor. The Journal of Physical Chemistry. A, 120(43), 8606-8612. DOI: 10.1021/acs.jpca.6b09644 [details]
- Kiawi, D. M., Chernyy, V., Oomens, J., Buma, W. J., Jamshidi, Z., Visscher, L., ... Bakker, J. M. (2016). Water Dissociation upon Adsorption onto Free Iron Clusters Is Size Dependent. The Journal of Physical Chemistry Letters, 7(13), 2381-2387. DOI: 10.1021/acs.jpclett.6b00891 [details]
- Maltseva, E., Petrignani-Taube, A., Candian, A., Mackie, C. J., Huang, X., Lee, T. J., ... Buma, W. J. (2016). HIGH-RESOLUTION IR ABSORPTION SPECTROSCOPY OF POLYCYCLIC AROMATIC HYDROCARBONS IN THE 3 mu m REGION: ROLE OF PERIPHERY. Astrophysical Journal, 831(1). DOI: 10.3847/0004-637X/831/1/58 [details]
- Maltseva, E., Petrignani-Taube, A., Candian, A., Mackie, C. J., Huang, X., Lee, T. J., ... Buma, W. J. (2016). HIGH-RESOLUTION IR ABSORPTION SPECTROSCOPY OF POLYCYCLIC AROMATIC HYDROCARBONS: THE REALM OF ANHARMONICITY (vol 814, 23, 2015). Astrophysical Journal, 820(1). DOI: 10.3847/0004-637X/820/1/81 [details]
- de Weerd, C., Gomez, L., Zhang, H., Buma, W. J., Nedelcu, G., Kovalenko, M. V., & Gregorkiewicz, T. (2016). Energy Transfer between Inorganic Perovskite Nanocrystals. The Journal of Physical Chemistry. C, 120(24), 13310-13315. DOI: 10.1021/acs.jpcc.6b04768 [details]
- Álvaro Galué, H., Oomens, J., Buma, W. J., & Redlich, B. (2016). Electron-flux infrared response to varying π-bond topology in charged aromatic monomers. Nature Communications, 7, . DOI: 10.1038/ncomms12633 [details / files]
- Mackie, C. J., Candian, A., Huang, X., Maltseva, E., Petrignani-Taube, A., Oomens, J., ... Tielens, A. G. G. M. (2016). The anharmonic quartic force field infrared spectra of five non-linear polycyclic aromatic hydrocarbons: Benz[a]anthracene, chrysene, phenanthrene, pyrene, and triphenylene. Journal of Chemical Physics, 145(8). DOI: 10.1063/1.4961438 [details]
- Balkowski, G., Szemik-Hojniak, A., Buma, W. J., Zhang, H., Deperasińska, I., Poisson, L., ... Oberda, K. (2015). Ultrafast excited-state dynamics of a cyano-substituted "proton sponge". The Journal of Physical Chemistry. A, 119(46), 11233-11240. DOI: 10.1021/acs.jpca.5b06631 [details]
- Ding, Y., Wu, F., Zhang, Y., Liu, X., de Jong, E. M. L. D., Gregorkiewicz, T., ... Zhang, H. (2015). Interplay between Static and Dynamic Energy Transfer in Biofunctional Upconversion Nanoplatforms. The Journal of Physical Chemistry Letters, 6(13), 2518-2523. DOI: 10.1021/acs.jpclett.5b00999 [details]
- Domingos, S. R., Hartl, F., Buma, W. J., & Woutersen, S. (2015). Elucidating the structure of chiral molecules by using amplified vibrational circular dichroism: from theory to experimental realization. ChemPhysChem, 16(16), 3363-3373. DOI: 10.1002/cphc.201500551 [details]
- Goswami, M., Lyaskovskyy, V., Domingos, S. R., Buma, W. J., Woutersen, S., Troeppner, O., ... de Bruin, B. (2015). Characterization of Porphyrin-Co(III)-'Nitrene Radical' Species Relevant in Catalytic Nitrene Transfer Reactions. Journal of the American Chemical Society, 137(16), 5468-5479. DOI: 10.1021/jacs.5b01197 [details]
- Liu, K., Holz, J. A., Ding, Y., Liu, X., Zhang, Y., Tu, L., ... Zhang, H. (2015). Targeted labeling of early-stage tumor spheroid in chorioallantoic membrane model with upconversion nanoparticles. Nanoscale, 7(5), 1596-1600. DOI: 10.1039/c4nr05638h [details / files]
- Maltseva, E., Petrignani, A., Candian, A., Mackie, C. J., Huang, X., Lee, T. J., ... Buma, W. J. (2015). High-resolution IR absorption spectroscopy of polycyclic aromatic hydrocarbons: the realm of anharmonicity. Astrophysical Journal, 814(1), . DOI: 10.1088/0004-637X/814/1/23 [details / files]
- Nicu, V. P., Domingos, S. R., Strudwick, B. H., Brouwer, A. M., & Buma, W. J. (2015). Interplay of exciton coupling and large-amplitude motions in the vibrational circular dichroism spectrum of dehydroquinidine. Chemistry: A European Journal, 22(2), 704-715. DOI: 10.1002/chem.201503250 [details]
- Tan, E. M. M., Amirjalayer, S., Smolarek, S., Vdovin, A., Zerbetto, F., & Buma, W. J. (2015). Fast photodynamics of azobenzene probed by scanning excited-state potential energy surfaces using slow spectroscopy. Nature Communications, 6, . DOI: 10.1038/ncomms6860 [details / files]
- Kiawi, D. M., Bakker, J. M., Oomens, J., Buma, W. J., Jamshidi, Z., Visscher, L., & Waters, L. B. F. M. (2015). Water adsorption on free cobalt cluster cations. The Journal of Physical Chemistry. A, 119(44), 10828-10837. DOI: 10.1021/acs.jpca.5b07119 [details]
- Mackie, C. J., Candian, A., Huang, X., Maltseva, E., Petrignani, A., Oomens, J., ... Tielens, A. G. G. M. (2015). The anharmonic quartic force field infrared spectra of three polycyclic aromatic hydrocarbons: naphthalene, anthracene, and tetracene. Journal of Chemical Physics, 143, . DOI: 10.1063/1.4936779 [details]
- McMahon, S., Amirjalayer, S., Buma, W. J., Halpin, Y., Long, C., Rooney, A. D., ... Pryce, M. T. (2015). An investigation into the photochemistry of, and the electrochemically induced CO-loss from, [(CO)(5)MC(OMe)Me](M = Cr or W) using low-temperature matrix isolation, picosecond infrared spectroscopy, cyclic voltammetry, and time-dependent density functional theory. Dalton Transactions, 44(35), 15424-15434. DOI: 10.1039/c5dt01568e [details]
- Domingos, S. R., Sanders, H. J., Hartl, F., Buma, W. J., & Woutersen, S. (2014). Switchable Amplification of Vibrational Circular Dichroism as a Probe of Local Chiral Structure. Angewandte Chemie, International Edition, 53(51), 14042-14045. DOI: 10.1002/anie.201407376 [details]
- Domingos, S. R., Huerta-Viga, A., Baij, L., Amirjalayer, S., Dunnebier, D. A. E., Walters, A. J. C., ... Woutersen, S. (2014). Amplified Vibrational Circular Dichroism as a Probe of Local Biomolecular Structure. Journal of the American Chemical Society, 136(9), 3530-3535. DOI: 10.1021/ja411405s [details]
- Liu, K., Wang, Y., Kong, X., Liu, X., Zhang, Y., Tu, L., ... Zhang, H. (2014). Multispectral upconversion luminescence intensity ratios for ascertaining the tissue imaging depth. Nanoscale, 6(15), 9257-9263. DOI: 10.1039/c4nr02090a [details / files]
- Tan, E. M. M., Hilbers, M., & Buma, W. J. (2014). Excited-State Dynamics of Isolated and Microsolvated Cinnamate-Based UV-B Sunscreens. The Journal of Physical Chemistry Letters, 5(14), 2464-2468. DOI: 10.1021/jz501140b [details]
- Tan, E. M. M., Amirjalayer, S., Mazzella, P., Bakker, B. H., van Maarseveen, J. H., Bieraugel, H., & Buma, W. J. (2014). Molecular Beam and ab Initio Studies of Photoactive Yellow Protein Chromophores: Influence of the Thioester Functionality and Single Bond Rotation. The journal of Physical Chemistry. B, 118(43), 12395-12403. DOI: 10.1021/jp5075169 [details]
- van der Loop, T. H., Ruesink, F., Amirjalayer, S., Sanders, H. J., Buma, W. J., & Woutersen, S. (2014). Unraveling the Mechanism of a Reversible Photoactivated Molecular Proton Crane. The journal of Physical Chemistry. B, 118(45), 12965-12971. DOI: 10.1021/jp508911v [details]
- Conyard, J., Heisler, I. A., Browne, W. R., Feringa, B. L., Amirjalayer, S., Buma, W. J., ... Meech, S. R. (2014). Ultrafast Excited State Dynamics in 9,9 '-Bifluorenylidene. The Journal of Physical Chemistry. A, 118(31), 5961-5968. DOI: 10.1021/jp504391s [details]
- Manton, J. C., Amirjalayer, S., Coleman, A. C., McMahon, S., Harvey, E. C., Greetham, G. M., ... Long, C. (2014). Excited State Evolution towards ligand loss and ligand chelation at group 6 metal carbonyl centres. Dalton Transactions, 43(47), 17797-17805. . DOI: 10.1039/c4dt01544d [details / files]
- Liu, X., Zheng, M., Kong, X., Zhang, Y., Zeng, Q., Sun, Z., ... Zhang, H. (2013). Separately doped upconversion-C60 nanoplatform for NIR imaging-guided photodynamic therapy of cancer cells. Chemical Communications, 49(31), 3224-3226. DOI: 10.1039/c3cc41013g [details / files]
- Panman, M. R., Bakker, B. H., den Uyl, D., Kay, E. R., Leigh, D. A., Buma, W. J., ... Woutersen, S. (2013). Water lubricates hydrogen-bonded molecular machines. Nature Chemistry, 5(11), 929-934. DOI: 10.1038/NCHEM.1744 [details]
- Tan, E. M. M., Amirjalayer, S., Bakker, B. H., & Buma, W. J. (2013). Excited state dynamics of Photoactive Yellow Protein chromophores elucidated by high-resolution spectroscopy and ab initio calculations. Faraday Discussions, 163, 321-340. DOI: 10.1039/c2fd20139a [details] [PDF]
- Tan, E. M. M., Amirjalayer, S., Smolarek, S., Vdovin, A., Rijs, A. M., & Buma, W. J. (2013). Conformational Heterogeneity of Methyl 4-Hydroxycinnamate: A Gas-Phase UV-IR Spectroscopic Study. The journal of Physical Chemistry. B, 117(17), 4798-4805. DOI: 10.1021/jp312624e [details]
- de Boer, W. D. A. M., de Jong, E. M. L. D., Timmerman, D., Gregorkiewicz, T., Zhang, H., Buma, W. J., ... Yassievich, I. N. (2013). Carrier dynamics in Si nanocrystals in an SiO2 matrix investigated by transient light absorption. Physical Review B, 88(15), . DOI: 10.1103/PhysRevB.88.155304 [details] [PDF]
- Brauer, N. B., Smolarek, S., Loginov, E., Mateo, D., Hernando, A., Pi, M., ... Drabbels, M. (2013). Critical Landau Velocity in Helium Nanodroplets. Physical Review Letters, 111, 153002. DOI: 10.1103/PhysRevLett.111.153002 [details / files]
- Domingos, S. R., Luyten, H., van Anrooij, F., Sanders, H. J., Bakker, B. H., Buma, W. J., ... Woutersen, S. (2013). An optically transparent thin-layer electrochemical cell for the study of vibrational circular dichroism of chiral redox-active molecules. Review of Scientific Instruments, 84(3), 033103. DOI: 10.1063/1.4793722 [details] [PDF]
- Panman, M. R., Bodis, P., Shaw, D. J., Bakker, B. H., Newton, A. C., Kay, E. R., ... Woutersen, S. (2012). Time-resolved vibrational spectroscopy of a molecular shuttle. Physical Chemistry Chemical Physics, 14(6), 1865-1875. DOI: 10.1039/c1cp22146a [details]
- de Boer, W. D. A. M., Timmerman, D., Gregorkiewicz, T., Zhang, H., Buma, W. J., Poddubny, A. N., ... Yassievich, I. N. (2012). Self-trapped exciton state in Si nanocrystals revealed by induced absorption. Physical Review B, 85(16), . DOI: 10.1103/PhysRevB.85.161409 [details]
- Almasian, M., Grzetic, J., Berden, G., Bakker, B., Buma, W. J., & Oomens, J. (2012). Gas-phase infrared spectrum of the anionic GFP-chromophore. International Journal of Mass Spectrometry, 330-332, 118-123. DOI: 10.1016/j.ijms.2012.08.017 [details]
- Almasian, M., Grzetic, J., van Maurik, J., Steill, J. D., Berden, G., Ingemann, S., ... Oomens, J. (2012). Non-equilibrium isomer distribution of the gas-phase photoactive yellow protein chromophore. The Journal of Physical Chemistry Letters, 3(16), 2259-2263. DOI: 10.1021/jz300780t [details]
- Domingos, S. R., Pereira Silva, P. S., Buma, W. J., Garcia, M. H., Lopes, N. C., Paixao, J. A., ... Woutersen, S. (2012). Amplification of the linear and nonlinear optical response of a chiral molecular crystal. Journal of Chemical Physics, 136(13), . DOI: 10.1063/1.3697842 [details / files]
- Domingos, S. R., Panman, M. R., Bakker, B. H., Hartl, F., Buma, W. J., & Woutersen, S. (2012). Amplifying vibrational circular dichroism by manipulation of the electronic manifold. Chemical Communications, 48(3), 353-355. DOI: 10.1039/c1cc15369b [details]
- Bodis, P., Yeremenko, S., Berna, J., Buma, W. J., Leigh, D. A., & Woutersen, S. (2011). Bimodal dynamics of mechanically constrained hydrogen bonds revealed by vibrational photon echoes. Journal of Chemical Physics, 134(13), 134504. DOI: 10.1063/1.3569761 [details] [PDF]
- Rijs, A. M., Kay, E. R., Leigh, D. A., & Buma, W. J. (2011). IR spectroscopy on jet-cooled isolated two-station rotaxanes. The Journal of Physical Chemistry. A, 115(34), 9669-9675. DOI: 10.1021/jp200909v [details]
- Smolarek, S., Vdovin, A., Rijs, A., van Walree, C. A., Zgierski, M. Z., & Buma, W. J. (2011). High-resolution spectroscopy of jet-cooled 1,1 '-diphenylethylene: electronically excited and ionic states of a prototypical cross-conjugated system. The Journal of Physical Chemistry. A, 115(34), 9399-9410. DOI: 10.1021/jp111127g [details]
- Smolarek, S., Vdovin, A., Tan, E. M. M., & Buma, W. J. (2011). Vibrational and electronic spectroscopy of the 4-hydroxystyrene-CO2 cluster and its hydrate: a para-coumaric acid impostor. The journal of Physical Chemistry. B, 115(5), 1275-1281. DOI: 10.1021/jp109895c [details]
- Smolarek, S., Vdovin, A., Tan, E. M. M., de Groot, M., & Buma, W. J. (2011). Spectroscopy and dynamics of methyl-4-hydroxycinnamate: the influence of isotopic substitution and water complexation. Physical Chemistry Chemical Physics, 13(10), 4393-4399. DOI: 10.1039/c0cp02221g [details]
- Wang, Y., Liu, K., Liu, X., Dohnalová, K., Gregorkiewicz, T., Kong, X., ... Zhang, H. (2011). Critical shell thickness of core/shell upconversion luminescence nanoplatform for FRET application. The Journal of Physical Chemistry Letters, 2(17), 2083-2088. DOI: 10.1021/jz200922f [details]
- Brauer, N. B., Smolarek, S. D., Zhang, X., Buma, W. J., & Drabbels, M. (2011). Electronic spectroscopy of aniline ions embedded in helium nanodroplets. The Journal of Physical Chemistry Letters, 2(13), 1563-1566. DOI: 10.1021/jz200632s [details]
- Bremmer, R. H., de Bruin, D. M., de Joode, M., Buma, W. J., van Leeuwen, T. G., & Aalders, M. C. G. (2011). Biphasic Oxidation of Oxy-Hemoglobin in Bloodstains. PLoS One, 6(7), e21845-e21845. DOI: 10.1371/journal.pone.0021845 [details] [PDF]
- Panman, M. R., Bodis, P., Shaw, D. J., Bakker, B. H., Newton, A. C., Kay, E. R., ... Woutersen, S. (2010). Operation mechanism of a molecular machine revealed using time-resolved vibrational spectroscopy. Science, 328(5983), 1255-1258. DOI: 10.1126/science.1187967 [details]
- Rijs, A. M., Sändig, N., Blom, M. N., Oomens, J., Hannam, J. S., Leigh, D. A., ... Buma, W. J. (2010). Controlled hydrogen-bond breaking in a rotaxane by discrete solvation. Angewandte Chemie, International Edition, 49(23), 3896-3900. DOI: 10.1002/anie.201001231 [details]
- Smolarek, S., Brauer, N. B., Buma, W. J., & Drabbels, M. (2010). IR spectroscopy of molecular ions by nonthermal ion ejection from helium nanodroplets. Journal of the American Chemical Society, 132(40), 14086-14091. DOI: 10.1021/ja1034655 [details]
- Smolarek, S., Rijs, A. M., Buma, W. J., & Drabbels, M. (2010). Absorption spectroscopy of adenine, 9-methyladenine, and 2-aminopurine in helium nanodroplets. Physical Chemistry Chemical Physics, 12(48), 15600-15606. DOI: 10.1039/c0cp00746c [details]
- Smolarek, S., Vdovin, A., Perrier, D. L., Smit, J. P., Drabbels, M., & Buma, W. J. (2010). High-resolution excitation and absorption spectroscopy of gas-phase p-coumaric acid: unveiling an elusive chromophore. Journal of the American Chemical Society, 132(18), 6315-6317. DOI: 10.1021/ja101668v [details]
- Tu, L., Wang, Y., Yang, Y., Bakker, B. H., Kong, X., Brouwer, A. M., ... Zhang, H. (2010). Spectroscopic study of the authentic emitter of AMPPD chemiluminescence in alkaline aqueous solution. Physical Chemistry Chemical Physics, 12(25), 6789-6794. DOI: 10.1039/b922244h [details]
- Wang, Y., Smolarek, S., Kong, X., Buma, W. J., Brouwer, A. M., & Zhang, H. (2010). Effect of surface related organic vibrational modes in luminescent upconversion dynamics of rare earth ions doped nanoparticles. Journal of Nanoscience and Nanotechnology, 10(11), 7149-7153. DOI: 10.1166/jnn.2010.2878 [details]
- Zhang, Y., Zeng, Q., Sun, Y., Liu, X., Tu, L., Kong, X., ... Zhang, H. (2010). Multi-targeting single fiber-optic biosensor based on evanescent wave and quantum dots. Biosensors & Bioelectronics, 26(1), 149-154. DOI: 10.1016/j.bios.2010.05.032 [details]
- de Boer, W. D. A. M., Timmerman, D., Dohnalová, K., Yassievich, I. N., Zhang, H., Buma, W. J., & Gregorkiewicz, T. (2010). Red spectral shift and enhanced quantum efficiency in phonon-free photoluminescence from silicon nanocrystals. Nature Nanotechnology, 5(12), 878-884. DOI: 10.1038/nnano.2010.236 [details]
- Schwartz, E., Domingos, S. R., Vdovin, A., Koepf, M., Buma, W. J., Cornelissen, J. J. L. M., ... Woutersen, S. (2010). Direct access to polyisocyanide screw sense using vibrational circular dichroism. Macromolecules, 43(19), 7931-7935. DOI: 10.1021/ma101601e [details]
- de Klerk, J., van Stokkum, I. H. M., Szemik-Hojniak, A., Deperasińska, I., Gooijer, C., Zhang, H., ... Ariese, F. (2010). Excited state processes of 2-butylamino-6-methyl-4-nitropyridine N-oxide in nonpolar solvents. A transient absorption spectroscopy study. The Journal of Physical Chemistry. A, 114(12), 4045-4050. DOI: 10.1021/jp909468h [details]
- Bodis, P., Panman, M. R., Bakker, B. H., Mateo-Alonso, A., Prato, M., Buma, W. J., ... Woutersen, S. (2009). Two-dimensional vibrational spectroscopy of rotaxane-based molecular machines. Accounts of Chemical Research, 42(9), 1462-1469. DOI: 10.1021/ar9000845 [details]
- Rijs, A. M., Compagnon, I., Oomens, J., Hannam, J. S., Leigh, D. A., & Buma, W. J. (2009). Stiff, and sticky in the right places: Binding interactions in isolated mechanically interlocked molecules probed by mid-infrared spectroscopy. Journal of the American Chemical Society, 131(7), 2428-2429. DOI: 10.1021/ja808788c [details]
- Smolarek, S., Rijs, A. M., Hannam, J. S., Leigh, D. A., Drabbels, M., & Buma, W. J. (2009). Conformational flexibility of a rotaxane thread probed by electronic spectroscopy in helium nanodroplets. Journal of the American Chemical Society, 131(36), 12902-12903. DOI: 10.1021/ja905973v [details]
- de Groot, M., Field, R. W., & Buma, W. J. (2009). Interference in acetylene intersystem crossing acts as the molecular analog of Young's double-slit experiment. Proceedings of the National Academy of Sciences of the United States of America, 106(8), 2510-2514. DOI: 10.1073/pnas.0809159106 [details]
- Altoè, P., Haraszkiewicz, N., Gatti, F. G., Wiering, P. G., Frochot, C., Brouwer, A. M., ... Garavelli, M. (2009). Multistate photo-induced relaxation and photoisomerization ability of fumaramide threads: A computational and experimental study. Journal of the American Chemical Society, 131(1), 104-117. DOI: 10.1021/ja802531j [details]
- Prokofiev, A. A., Moskalenko, A. S., Yassievich, I. N., de Boer, W. D. A. M., Timmerman, D., Zhang, H., ... Gregorkiewicz, T. (2009). Direct bandgap optical transitions in Si nanocrystals. JETP Letters, 90(12), 758-762. DOI: 10.1134/S0021364009240059 [details]
- Jagesar, D. C., Hartl, F., Buma, W. J., & Brouwer, A. M. (2008). Infrared study of intercomponent interactions in a switchable hydrogen-bonded rotaxane. Chemistry - A European Journal, 14(6), 1935-1946. DOI: 10.1002/chem.200701531 [details]
- Koopman, L., Brouwer, N., Heck, A., & Buma, W. J. (2008). Remedial mathematics for quantum chemistry. Journal of Chemical Education, 85(9), 1233-1236. DOI: 10.1021/ed085p1233 [details]
- Rijs, A. M., Crews, B. O., de Vries, M. S., Hannam, J. S., Leigh, D. A., Fanti, M., ... Buma, W. J. (2008). Shaping of a conformationally flexible molecular structure for spectroscopy. Angewandte Chemie, International Edition, 47(17), 3174-3179. DOI: 10.1002/anie.200705627 [details]
- de Groot, M., Gromov, E. V., Köppel, H., & Buma, W. J. (2008). High-resolution spectroscopy of methyl 4-hydroxycinnamate and its hydrogen-bonded water complex. The journal of Physical Chemistry. B, 112(14), 4427-4434. DOI: 10.1021/jp7101308 [details]
- Nosenko, Y., Wiosna-Sałyga, G., Kunitski, M., Petkova, I., Singh, A., Buma, W. J., ... Waluk, J. (2008). Proton transfer with a twist? Femtosecond dynamics of 7-(2-pyridyl)indole in condensed phase and in supersonic jets. Angewandte Chemie, International Edition, 47(32), 6037-6040. DOI: 10.1002/anie.200801350 [details]
- de Groot, M., & Buma, W. J. (2009). Moleculaire vivisectie, Youngs dubbelspleetexperiment en een schizofreen molecuul. Nederlands Tijdschrift voor Natuurkunde, 75(7), 274-278. [details]
- Buma, W.J. (member) (2015-2016): Member Editorial Advisory Board ChemPhysChem (External organisation).
- Buma, W.J. (participant) (2016 - 9-2016): Member Senate University of Amsterdam (other).
- Buma, W.J. (participant) (2016): Chairman John van Geuns Foundation (other).
- Buma, W.J. (participant) (2016): Scientific Director Holland Research School of Molecular Chemistry (other).
- Buma, W.J. (participant) (2016): Secretary “Stichting Beta Plus” (other).
- Buma, W.J. (speaker) (25-4-2016): Fast photodynamics probed by slow spectroscopy, Multi-Responsive Photochromes, Nantes, France.
- Buma, W.J. (speaker) (6-12-2016): High-resolution laser spectroscopy of photoactive materials: light on the dark side of the force, CHAINS 2016, Veldhoven, Netherlands.
- Buma, W.J. (speaker) (8-4-2016): Light on photoactive molecules: electrons and nuclei at work, FYSICA 2016, Nijmegen, Netherlands.
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