caa a22 4500 60548855X CHVBK 20210128100456.0 cr unu---uuuuu 210128e20151101xx s 000 0 eng 10.1007/s00214-015-1736-1 doi (NATIONALLICENCE)springer-10.1007/s00214-015-1736-1 Determination of the collective modes from the quantum-mechanical time-correlation functions [Elektronische Daten] [Bing Gu, Sophya Garashchuk] Theoretical characterization of vibrational spectra for large molecular systems often comes from the normal modes analysis derived from the quadratic approximation of the potential energy surface near its minimum. The normal modes of motion provide accurate representation of low-energy collective motion within a system near equilibrium, but they may be inadequate at high energies or for strongly anharmonic systems. In this article, the collective modes of motion are examined from the time-dependent perspective. It is shown that the imaginary part of the quantum-mechanical position-position correlation functions contains all the information about the collective modes of motion without the harmonic approximation on the potential energy of a system. Springer-Verlag Berlin Heidelberg, 2015 Position-position correlation functions nationallicence Quantum-mechanical time correlation nationallicence Collective vibrational modes nationallicence Gu Bing Department of Chemistry and Biochemistry, University of South Carolina, 29208, Columbia, SC, USA aut Garashchuk Sophya Department of Chemistry and Biochemistry, University of South Carolina, 29208, Columbia, SC, USA aut Theoretical Chemistry Accounts Springer Berlin Heidelberg 134/11(2015-11-01), 1-9 1432-881X 134:11<1 2015 134 214 https://doi.org/10.1007/s00214-015-1736-1 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00214-015-1736-1 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Gu Bing Department of Chemistry and Biochemistry, University of South Carolina, 29208, Columbia, SC, USA aut NATIONALLICENCE 700 1- Garashchuk Sophya Department of Chemistry and Biochemistry, University of South Carolina, 29208, Columbia, SC, USA aut NATIONALLICENCE 773 0- Theoretical Chemistry Accounts Springer Berlin Heidelberg 134/11(2015-11-01), 1-9 1432-881X 134:11<1 2015 134 214