Tunneling in novel hydroxycarbenes  Page description

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Details of project

  
Identifier
81072
Type NN
Principal investigator Császár, Attila Géza
Title in Hungarian Alagúthatás újonnan előállítandó hidroxikarbénekben
Title in English Tunneling in novel hydroxycarbenes
Keywords in Hungarian hidroxikarbének, alagúthatás, szintézis, mátrixizoláció, spektroszkópia, molekuladinamika, szerkezetvizsgálat
Keywords in English hydroxycarbenes, tunneling, synthesis, matrix isolation, spectroscopy, molecular dynamics, structural studies
Discipline
Organic, Biomolecular, and Pharmaceutical Chemistry (Council of Physical Sciences)50 %
Ortelius classification: Intermedier chemistry
Physical Chemistry and Theoretical Chemistry (Council of Physical Sciences)50 %
Ortelius classification: Quantum chemistry
Panel Chemistry 1
Department or equivalent Komplex Kémiai Rendszerek Kutatócsoport (Office for Research Groups Attached to Universities and Other Institutions)
Participants Czakó, Gábor
Furtenbacher, Tibor
Mátyus, Edit
Starting date 2009-09-01
Closing date 2014-08-31
Funding (in million HUF) 5.674
FTE (full time equivalent) 7.19
state closed project
Summary in Hungarian
Building on the complementary backgrounds and expertise of the Giessen (experimental organic chemists and spectroscopists) and the Budapest (computational quantum chemists) groups, we propose a joint program that uniquely combines the preparation, detection, and spectroscopic as well as computa-tional characterization of designed novel carbenes exhibiting enhanced hydrogen and possibly heavy-atom tunnelling under large barriers at low cryogenic temperatures (down to 6 K). The very low temperatures and the noble gas environment of cryogenic matrices are ideally suited for quantum chemical reaction rate and tunnelling (quantum reaction dynamics) studies on single ground-state surfaces. The proposed full- and reduced-dimensionality reaction dynamics computations are expected to guide new experiments and, when augmented with sophisticated electronic structure computations, should shed light on the factors that govern enhanced quantum mechanical tunnelling under large barriers near 0 K on timescales of minutes to days. Questions the proposed research aims to answer include: (a) how do electronic substituent effects alter the rates of H-tunnelling in novel unsaturated hydroxycarbenes; (b) how large a barrier can be afforded for observable H-tunnelling; and (c) can hydrogen bonding be used to tune the rate of H-tunneling?
Novel aspects of the proposed research program include: (a) systematic preparation of a series of electronically related substituted, currently unknown hydroxycarbenes; (b) development of synthetic routes to substituted hydroxycarbenes; (c) studying the electronic effects on tunnelling, utilizing the most advanced levels of quantum chemistry (including ground-breaking electronic structure, nuclear motion, and reaction dynamics computations); (d) variational determination of rovibrational spectra of carbenes containing five or more atoms and/or multiple minima on their PES; (e) quantum chemical computation of microcanonical rate constants based on the availability based on a time-independent machinery similar to that which allows determination of a nearly complete set of stationary rotational-vibrational wave functions and energy levels.
Summary
We propose a joint program that uniquely combines the preparation, detection, and spectroscopic as well as computational characterization of designed novel carbenes exhibiting enhanced hydrogen and possibly heavy-atom tunnelling under large barriers at low cryogenic temperatures. The very low temperatures and the noble gas environment of cryogenic matrices are ideally suited for quantum chemical reaction rate and tunnelling (quantum reaction dynamics) studies on single ground-state surfaces. The proposed full- and reduced-dimensionality reaction dynamics computations are expected to guide new experiments and, when augmented with sophisticated electronic structure computations, should shed light on the factors that govern enhanced quantum mechanical tunnelling under large barriers near 0 K on timescales of minutes to days. Questions the proposed research aims to answer include: (a) how do electronic substituent effects alter the rates of H-tunnelling in novel unsaturated hydroxycarbenes; (b) how large a barrier can be afforded for observable H-tunnelling; and (c) can hydrogen bonding be used to tune the rate of H-tunneling?
Novel aspects of the proposed research program include: (a) systematic preparation of a series of electronically related substituted, currently unknown hydroxycarbenes; (b) development of synthetic routes to substituted hydroxycarbenes; (c) studying the electronic effects on tunnelling, utilizing the most advanced levels of quantum chemistry (including ground-breaking electronic structure, nuclear motion, and reaction dynamics computations); (d) variational determination of rovibrational spectra of carbenes containing five or more atoms and/or multiple minima on their PES; (e) quantum chemical computation of microcanonical rate constants based on the availability based on a time-independent machinery similar to that which allows determination of a nearly complete set of stationary rotational-vibrational wave functions and energy levels.




 

Final report

  
Results in Hungarian
A giessen-i (profil: kísérleti szerves kémia, mátrixizolációs molekulaspektroszkópia) és a budapesti (profil: számítógépes kvantumkémia) csoportok egymást kiegészítő kutatási hátterére alapozott közös kutatómunka jelentős számú új alapkutatási eredményt hozott. A teljes spektrumú közös kutatómunka a hidroxikarbének kapcsán a szintézistől (beleértve a prekurzorok szintézisét) a detektáláson (mátrixizolációs IR spektroszkópia) keresztül a kísérleti eredmények elméleti értelmezéséig (kvantumkémiai elektronszerkezet és magmozgás számítások) terjedt. A kísérleti és elméleti módszerfejlesztések eredményeként az alábbi tudományos kérdésekre sikerült feleletet adni: (a) hogyan lehet előállítani akár bonyolultabb szerkezetű szubsztituált hidroxikarbéneket; (b) hogyan változtatják a szubsztituensekhez köthető elektroneffektusok a hidroxikarbének esetében az alagúthatás sebességét (félidejét); (c) mekkora az a legnagyobb reakciógát, mely esetében még kísérletileg észlelhető az alagúthatás a mátrixizolációs infravörös spektroszkópia által teremtett feltételek mellett; és (d) milyen elméleti, kvantumkémiai módszerekkel lehet közelítően, illetve pontosan számítani kis molekulák esetében az alagúthatást.
Results in English
The joint research efforts based on the complementary research expertise of the Giessen (profile: experimental organic chemistry, matrix isolation molecular spectroscopy) and Budapest (profile: computational quantum chemistry) teams resulted in a number of novel findings relevant for basic research. The full spectrum of the joint research effort extended from synthesis, including the synthesis of the precursors of the investigated molecules, and detection, basically matrix isolation IR spectroscopy, to theoretical interpretation of the experimental findings, based on sophisticated electronic structure and nuclear motion computations. Due to the considerable experimental and theoretical method developments we were able to answer the following questions: (a) how can one synthesize complex substituted hydroxicarbenes; (b) how do the substituent electronic effects alter the tunneling half lifes of hydroxycarbenes; (c) how large the tunneling barrier can be so that tunneling could be observed using matrix isolation infrared spectroscopy; and (d) which theoretical and quantum chemical methods can be used to study tunneling approximately and exactly.
Full text https://www.otka-palyazat.hu/download.php?type=zarobeszamolo&projektid=81072
Decision
Yes





 

List of publications

  
P. R. Schreiner, H. P. Reisenauer, E. Mátyus, A. G. Császár, A. Siddiqi, A. C. Simmonett, and W. D. Allen: Infrared Signatures of the NCCO Radical, Phys. Chem. Chem. Phys. 11, 10385-10390, 2009
P. R. Schreiner, H. P. Reisenauer, E. Mátyus, A. G. Császár, A. Siddiqi, A. C. Simmonett, and W. D. Allen: Infrared Signatures of the NCCO Radical, Phys. Chem. Chem. Phys., 2009
Dennis Gerbig, Hans Peter Reisenauer, Chia-Hua Wu, David Ley, Wesley D. Allen and Peter R. Schreiner: Phenylhydroxycarbene, J. Am. Chem. Soc., 2010
D. Gerbig, D. Ley, H. P. Reisenauer, P. R. Schreiner: Intramolecular hydroxycarbene C–H insertions: The curious case of (o-Methoxy)phenylhydroxycarbene, Beilstein J. Org. Chem., 2010
J. Sarka, A. G. Császár, and P. R. Schreiner: Do the Mercaptocarbene (H-C-S-H) and Selenocarbene (H-C-Se-H) Congeners of Hydroxycarbene (H-C-O-H) Undergo 1,2-H-Tunneling?, Coll. Czech Chem. Comm., 2011
C. Fábri, E. Mátyus, and A. G. Császár: Rotating Full- and Reduced-Dimensional Quantum Chemical Models of Molecules, J. Chem. Phys., 2011
Schreiner, PR, Reisenauer, HP, Ley, D, Gerbig, D, Wu, CH, Allen, WD: Methylhydroxycarbene: Tunneling Control of a Chemical Reaction, Science, 2011
Gerbig D, Ley D, Schreiner PR: Light- and Heavy-Atom Tunneling in Rearrangement Reactions of Cyclopropylcarbenes, Org. Lett., 2011
N. F. Zobov, S. V. Shirin, L. Lodi, B. C. Silva, J. Tennyson, A. G. Császár, and O. L. Polyansky: First-Principles Rotation-Vibration Spectrum of Water Above Dissociation, Chem. Phys. Lett., 2011
C. Fábri, A. G. Császár, and G. Czakó: Reduced-Dimensional Quantum Computations for the Rotational-Vibrational Dynamics of F--CH4 and F--CH2D2, J. Phys. Chem. A 117, 6975-6983, 2013
T. Szidarovszky and A. G. Császár, ,: Low-Lying Quasibound Rovibrational States of H216O, Mol. Phys. 111(14-15), 2131-2146, 2013
David Ley, Dennis Gerbig, and Peter R. Schreiner: Tunneling Control of Chemical Reactions: C-H Insertion versus H-Tunneling in tert-Butylhydroxycarbene, Chem. Sci. 4, 677-684, 2013
David Ley, Dennis Gerbig, and Peter R. Schreiner: Tunneling Control of Chemical Reactions - The Organic Chemist's Perspective, Org. Biomol. Chem. 10, 3781-3790, 2012
David Ley, Dennis Gerbig, J. Philipp Wagner, Hans Peter Reisenauer, and Peter R. Schreiner: Cyclopropylhydroxycarbene, J. Am. Chem. Soc. 133, 13614-13621, 2011
Dennis Gerbig, Hans Peter Reisenauer, Chia-Hua Wu, David Ley, Wesley D. Allen and Peter R. Schreiner: Phenylhydroxycarbene, J. Am. Chem. Soc. 132, 7273-7275, 2010
J. Sarka, A. G. Császár, and P. R. Schreiner: Do the Mercaptocarbene (H-C-S-H) and Selenocarbene (H-C-Se-H) Congeners of Hydroxycarbene (H-C-O-H) Undergo 1,2-H-Tunneling?, Coll. Czech Chem. Comm. 76, 645-667, 2011
C. Fábri, E. Mátyus, and A. G. Császár: Rotating Full- and Reduced-Dimensional Quantum Chemical Models of Molecules, J. Chem. Phys. 134, 074105, 2011
Schreiner, PR, Reisenauer, HP, Ley, D, Gerbig, D, Wu, CH, Allen, WD: Methylhydroxycarbene: Tunneling Control of a Chemical Reaction, Science, 332, 1300-1303, 2011
Gerbig D, Ley D, Schreiner PR: Light- and Heavy-Atom Tunneling in Rearrangement Reactions of Cyclopropylcarbenes, Org. Lett. 13, 3526-3529, 2011
N. F. Zobov, S. V. Shirin, L. Lodi, B. C. Silva, J. Tennyson, A. G. Császár, and O. L. Polyansky: First-Principles Rotation-Vibration Spectrum of Water Above Dissociation, Chem. Phys. Lett. 507, 48-51, 2011
C. Fábri, E. Mátyus, T. Furtenbacher, L. Nemes, B. Mihály, T. Zoltáni, A. G. Császár: Variational quantum mechanical and active database approaches to the rotational-vibrational spectroscopy of ketene, H2CCO, J. Chem. Phys. 135, 094307, 2011
D. Ley, D. Gerbig, P. R. Schreiner: Durch die Wand – Tunnelkontrolle chemischer Reaktionen, Nachr. Chem. 59, 1139–1141, 2012
A. G. Császár, G. Czakó, T. Furtenbacher, E. Mátyus, C. Fábri, T. Szidarovszky, I. Szabó, J. Sarka: Molecular structure and dynamics, Magy. Kém. Foly. 118, 181-189, 2012
T. Szidarovszky and A. G. Császár: Low-Lying Quasibound Rovibrational States of H216O, Mol. Phys. 111(14-15), 2131-2146, 2013
C. Fábri, E. Mátyus, A. G. Császár: Numerically constructed internal-coordinate Hamiltonian with Eckart embedding and its application for the inversion tunneling of ammonia, Spectrochim. Acta A 119, 84-89, 2014
C. Fábri, J. Sarka, A. G. Császár: Communication: Rigidity of the molecular ion H5+, J. Chem. Phys. 140, 051101, 2014
T. Furtenbacher, P. Árendás, G. Mellau, A. G. Császár: Simple molecules as complex systems, Sci. Rep. 4, 4654, 2014
P. R. Schreiner, J. P. Wagner, H. P. Reisenauer, D. Gerbig, D. Ley, J. Sarka, A. G. Császár, A. Vaughn, and W. D. Allen: Domino Tunneling, Nature Chem., submitted for publication, 2014




 

Events of the project

  
2013-01-07 08:21:38
Résztvevők változása
2011-01-17 13:22:26
Résztvevők változása



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