Results 21 to 30 of about 207,343 (281)

Intramolecular OHO Hydrogen Bonding in Dibenzoylmethane Enol: Raman Spectroscopic and Quantum Chemical Study

Micro, 2023
In the present work, the intramolecular O-H···O hydrogen bonding in 3-hydroxy-1,3-diphenylprop-2-en-1-one (keto-enol form of dibenzoylmethane, DBM) was investigated.
Boris A. Kolesov, Elena A. Pritchina, Aleksey Ya. Tikhonov   +2 more
doaj   +1 more source

Mechanism for Degradation of Nafion in PEM Fuel Cells from Quantum Mechanics Calculations [PDF]

, 2011
We report results of quantum mechanics (QM) mechanistic studies of Nafion membrane degradation in a polymer electrolyte membrane (PEM) fuel cell. Experiments suggest that Nafion degradation is caused by generation of trace radical species (such as OH ...
Goddard, William A., III, Liu, Wei-Guang, Merinov, Boris V., Sha, Yao, Shirvanian, Pezhman, Yu, Ted H.   +5 more
core   +1 more source

Proton-mediated photoprotection mechanism in photosystem II

Frontiers in Plant Science, 2022
Photo-induced charge separation, which is terminated by electron transfer from the primary quinone QA to the secondary quinone QB, provides the driving force for O2 evolution in photosystem II (PSII).
Yu Sugo, Hiroshi Ishikita, Hiroshi Ishikita   +2 more
doaj   +1 more source

Superprotonic phase transition of CsHSO4: A molecular dynamics simulation study [PDF]

, 2005
The superprotonic phase transition (phase II --> phase I; 414 K) of cesium hydrogen sulfate, CsHSO4, was simulated using molecular dynamics with the "first principles" MSXX force field (FF).
Chisholm, Calum R. I., Goddard, William A., III, Haile, Sossina M., Jang, Yun Hee   +3 more
core   +1 more source

Low-barrier hydrogen bonds in enzyme cooperativity

Nature, 2019
The underlying molecular mechanisms of cooperativity and allosteric regulation are well understood for many proteins, with haemoglobin and aspartate transcarbamoylase serving as prototypical examples1,2. The binding of effectors typically causes a structural transition of the protein that is propagated through signalling pathways to remote sites and ...
Dai, Shao-Bo, Funk, Lisa Marie, Rabe von Pappenheim, Fabian, Sautner, Viktor, Paulikat, Mirko, Schröder, Benjamin, Uranga, Jon, Mata, Ricardo A., Tittmann, Kai   +8 more
openaire   +4 more sources

Effect of quantum nuclear motion on hydrogen bonding [PDF]

, 2014
This work considers how the properties of hydrogen bonded complexes, D-H....A, are modified by the quantum motion of the shared proton. Using a simple two-diabatic state model Hamiltonian, the analysis of the symmetric case, where the donor (D) and ...
Bijyalaxmi Athokpam, Christiaan Bekker, Cleland W. W., Coulson C., Geru I., Iachello F., Köppel H., Ross H. McKenzie, Sai G. Ramesh   +8 more
core   +2 more sources

Mechanism of Selective Ammoxidation of Propene to Acrylonitrile on Bismuth Molybdates from Quantum Mechanical Calculations [PDF]

, 2010
In order to understand the mechanism for selective ammoxidation of propene to acrylonitrile by bismuth molybdates, we report quantum mechanical studies (using the B3LYP flavor of density functional theory) for the various steps involved in converting the
Goddard, William A. III, Oxgaard, Jonas, Pudar, Sanja   +2 more
core   +2 more sources

Hydrogen Bonding Constrains Free Radical Reaction Dynamics at Serine and Threonine Residues in Peptides [PDF]

, 2014
Free radical-initiated peptide sequencing (FRIPS) mass spectrometry derives advantage from the introduction of highly selective low-energy dissociation pathways in target peptides.
Adamson J. T., Anh N. T., Anusiewicz I., Anusiewicz I., Bagheri-Majdi E., Bakhtiar R., Barlow C. K., Barlow C. K., Bogdanov B., Chamot-Rooke J., Chang Ho Sohn, Chen X., Chu I. K., Cooper H. J., Cui W., Daniel A. Thomas, Diedrich J. K., Diedrich J. K., Frison G., Fu A.-p., Gronert S., Hodyss R., Hopkinson A. C., Håkansson K., Iavarone A. T., Izgorodina E. I., J. L. Beauchamp, Jinshan Gao, Ke Y., Kim T.-Y., Kruger N. A., Kruger N. A., Lam A. K. Y., Laskin J., Laskin J., Laskin J., Lee J., Lee J., Lee M., Lee M., Little D. P., Ly T., Ly T., Ly T., Marzluff E. M., Marzluff E. M., Masterson D. S., Miao R., Moore B., Moore B. N., Osburn S., Paizs B., Petrotchenko E. V., Ryzhov V., Sawicka A., Sawicka A., Schaftenaar G., Senko M. W., Shen Y., Shi S. D. H., Shukla A. K., Simon M. D., Simons J., Siuti N., Skurski P., Sobczyk M., Sobczyk M., Sobczyk M., Sobczyk M., Sohn C. H., Sun Q., Sun Q., Syka J. E. P., Syrstad E., Syrstad E. A., Syrstad E. A., Tao Y., Thompson M. S., Tureček F., Tureček F., Tureček F., Tureček F., Tureček F., Wee S., Wee S., Wee S., Wendler K., Xia Y., Yin H., Zhang L., Zhang X., Zhang X., Zhao Y., Zhao Y., Zhao Y., Zubarev R. A., Zubarev R. A., Zubarev R. A., Zubarev R. A.   +98 more
core   +1 more source

On the electronic nature of low-barrier hydrogen bonds in enzymatic reactions [PDF]

Proceedings of the National Academy of Sciences, 1998
The electronic nature of low-barrier hydrogen bonds (LBHBs) in enzymatic reactions is discussed based on combined low temperature neutron and x-ray diffraction experiments and on high levelab initiocalculations by using the model substrate benzoylacetone.
Schiøtt, Birgit; id_orcid 0000-0001-9937-1562, Iversen, B.B., Madsen, G.K.H., Larsen, F.K., Bruice, T.C.   +4 more
openaire   +3 more sources

Direct Observation of Early-stage Quantum Dot Growth Mechanisms with High-temperature Ab Initio Molecular Dynamics [PDF]

, 2015
Colloidal quantum dots (QDs) exhibit highly desirable size- and shape-dependent properties for applications from electronic devices to imaging. Indium phosphide QDs have emerged as a primary candidate to replace the more toxic CdSe QDs, but production of
Jensen, Klavs F., Kulik, Heather J., Xie, Lisi, Zhao, Qing   +3 more
core   +4 more sources