A combined experimental and computational investigation of the microscopic external heavy atom effect in van der Waals clusters.

The Journal of chemical physics

PubMedID: 15260613

Doyle RJ, Da Campo R, Taylor PR, Mackenzie SR. A combined experimental and computational investigation of the microscopic external heavy atom effect in van der Waals clusters. J Chem Phys. 2004;121(2):835-40.
We present a combined experimental and computational study of the external heavy atom effect in van der Waals clusters of para-difluorobenzene (pDFB) with rare-gas atoms. Experimentally, clustering with rare-gas atoms is observed to shorten significantly the S1 fluorescence lifetime compared with that of the pDFB monomer, an effect we interpret in terms of an enhancement of the S1-T1 intersystem crossing rate. In order to test the validity of this widely held assumption, we have calculated the S1-T1 spin-orbit coupling matrix elements in the X-pDFB complexes (X=Ne, Ar, Kr) using a multiconfigurational linear response approach.