Orientation and molecular orbital dependences in electronic relaxation collisions studied through van der Waals complexes

摘要

The orientation dependence in the spin changing collisions C$- 2$/H$-2$/O$-2$/(S$-1$/)$PLU@Ar$YLD@C$-2$/H$-2$/O$-2$/(T$- 1$/)$PLU@Ar and C$-2$/H$-2$/(S$-1$/)$PLU@Ar$YLD@C$-2$/H$- 2$/(T)$PLU@Ar has been examined by time-resolved laser induced fluorescence studies of the intersystem crossing rates in the C$- 2$/H$-2$/O$-2$/-Ar and C$-2$/H$-2$/-Ar complexes with different isomeric structures. It was found that when Ar interacts primarily with the n(O) orbital the S$-1$/$YLD@T$-1$/ transition rate is about two orders of magnitude faster than that induced by Ar interacting primarily with the $pi$+*$/(CO) orbital. On the other hand, the studies in acetylene show that the Ar induced intersystem crossing rate is nearly identical for both the $pi and $pi$+*$/ orbitals.