Abstract

An extensive picosecond CARS and spontaneous Raman investigation of temperature dependent dephasing of the totally symmetric vibrons in naphthalene (h8N), perdeuteronaphthalene (d8N), anthracene (h10A), and perdeuteroanthracene (d10A) crystals is presented. The low temperature picosecond decays, ranging from 128 to less than 10 ps, are due to vibrational relaxation by phonon emission. Unlike optical phonons in these crystals, vibron lifetimes of h8N and h10A do not decrease monotonically with frequency, a pattern which is observed in other molecular systems. The low temperature decay rate is proportional to the square of a cubic anharmonic matrix element and a density of difference states function which has a contribution from phonons and lower frequency vibrons. This function is evaluated for each substance and together with measured lifetimes yields matrix elements which are roughly equal for each vibron. We conclude that vibrational relaxation rates are controlled primarily by the density of final stat...

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.