AB-INITIO MODELS FOR MULTIPLE-HYDROGEN EXCHANGE - COMPARISON OF CYCLIC 4-CENTER AND 6-CENTER SYSTEMS

Journal article


Publication Details

Author(s): Heidrich D, van Eikema Hommes N, Schleyer P
Journal: Journal of Computational Chemistry
Publisher: Wiley-Blackwell
Publication year: 1993
Volume: 14
Journal issue: 10
Pages range: 1149-1163
ISSN: 0192-8651


Abstract


High-level ab initio calculations {QCISD(T)/6-311+G**//MP2(fu)/6-31+G**, with corrections for higher polarization [evaluated at MP2/6-311+G(3df,2p)] and DELTAZPE//MP2(fu)/6-31+G**, i.e., comparable to Gaussian-2 theory} indicate concerted mechanisms for double- and triple-hydrogen exchange reactions in HF and HCl dimers and trimers, in mixed dimers and trimers containing one NH3, and in mixed dimers of HF, HCl, and NH3 with formic acid. AU these reactions proceed via cyclic four- or six-center transition structures, the latter being generally more favorable. Calculated activation barriers (DELTAH(double dagger) at 0 K, kcal/mol) are 42.3 for (HF)2, 20.3 for (HF)3, 41.2 for (HCI)2, 25.6 for (HCI)3, 36.0 for NH3-HF, 10.6 for NH3(HF)2, 19.9 for NH3-HCI, 2.3 for NH3(HCI)2, 9.7 for HCO2H-HF, 7.0 for HCO2H-HCI, and 11.3, for HCO2H-NH3. The barriers are lower for the more ionic systems and when more ion pair character is present. (C) 1993 by John Wiley & Sons, Inc.



FAU Authors / FAU Editors

Schleyer, Paul Prof. Dr.
Naturwissenschaftliche Fakultät
van Eikema Hommes, Nico Dr.
Computer-Chemie-Centrum


External institutions
Universität Leipzig


How to cite

APA:
Heidrich, D., van Eikema Hommes, N., & Schleyer, P. (1993). AB-INITIO MODELS FOR MULTIPLE-HYDROGEN EXCHANGE - COMPARISON OF CYCLIC 4-CENTER AND 6-CENTER SYSTEMS. Journal of Computational Chemistry, 14(10), 1149-1163. https://dx.doi.org/10.1002/jcc.540141005

MLA:
Heidrich, Dietmar, Nico van Eikema Hommes, and Paul Schleyer. "AB-INITIO MODELS FOR MULTIPLE-HYDROGEN EXCHANGE - COMPARISON OF CYCLIC 4-CENTER AND 6-CENTER SYSTEMS." Journal of Computational Chemistry 14.10 (1993): 1149-1163.

BibTeX: 

Last updated on 2018-10-08 at 04:56