An intraline of conical intersections for methylamine

C. Levi, G. Halász, A. Vibók, I. Bar, Y. Zeiri, R. Kosloff, M. Baer

Research output: Contribution to journalArticle

26 Citations (Scopus)

Abstract

In this article are considered the conical intersections (ci's) related to the N-H bond in the methylamine, CH3NH2, molecule. The novel feature that was revealed is that the two lowest states 1 A′ and 1 A″ are coupled by a line of cis located in HC-NHH plane-a line that is formed by moving a single hydrogen on that plane while fixing the (six) other atoms. The validity of this line was proven first by studying the singularities of the (angular) nonadiabatic coupling terms and then by revealing the degeneracy points formed by the two interacting adiabatic potential energy surfaces (PESs). A theoretical analysis indicated that the line has to be a finite closed line. We also calculated the Berry phase for a contour that surrounds this line and found it to be 3.127 rad, namely, a value reasonably close to π. The existence of such lines of cis-instead of isolated cis (as exhibited by other n -atomic (n>3) molecules such as HNCO or C 2H2)-may enhance significantly the transition rate from an upper adiabatic state to a lower one. There are also numerical advantages in such situations, that is, if such a line is properly placed in that plane (like in the present case) the wave-packet treatment of the nuclei can be carried out employing a single diabatic PES instead of having to consider two coupled PESs.

Original languageEnglish
Article number244302
JournalThe Journal of Chemical Physics
Volume128
Issue number24
DOIs
Publication statusPublished - 2008

Fingerprint

Potential energy surfaces
intersections
Hydrogen
Fruit
potential energy
Wave packets
Molecules
fixing
wave packets
molecules
Atoms
nuclei
hydrogen
atoms
methylamine

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics
  • Medicine(all)

Cite this

An intraline of conical intersections for methylamine. / Levi, C.; Halász, G.; Vibók, A.; Bar, I.; Zeiri, Y.; Kosloff, R.; Baer, M.

In: The Journal of Chemical Physics, Vol. 128, No. 24, 244302, 2008.

Research output: Contribution to journalArticle

Levi, C. ; Halász, G. ; Vibók, A. ; Bar, I. ; Zeiri, Y. ; Kosloff, R. ; Baer, M. / An intraline of conical intersections for methylamine. In: The Journal of Chemical Physics. 2008 ; Vol. 128, No. 24.
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