Title: | BARELY FLUORESCENT MOLECULES I. TWIN DISCHARGE JET SPECTROSCOPY OF HSnCl |
Author(s): | Smith, Tony |
Contributor(s): | Tarroni, Riccardo ; Clouthier, Dennis ; Rothschopf, Gretchen K |
Subject(s): | Small molecules |
Abstract: | The divalent tin HSnCl transient molecule has been detected for the first time by LIF spectroscopy. HSnCl and DSnCl were produced in a twin discharge jet using separate precursor streams of SnH$_{4}$ and HCl (DCl), both diluted in high pressure argon. The \~{A}$^{1}$A$''$-\~{X}$^{1}$A$'$ spectrum of HSnCl consists of a single rotationally resolved 0-0 band with a very short fluorescence lifetime ($\sim$25 ns). In contrast, the spectrum of DSnCl exhibits three bands (0$_{0}^{\,0}$, 2$_{0}^{\,1}$ and 2$_{0}^{\,2}$) whose fluorescence lifetimes decrease from 400 ns (0$^{0}$) to less than 10 ns (2$^{2}$). Single vibronic level emission spectra have been recorded, providing information on all three vibrational modes in the ground state. Fluorescence hole burning experiments have shown that a few higher nonfluorescent levels are very short-lived but still detectable. Our detailed ab initio studies indicate that these molecules dissociate into SnCl + H on the excited state potential surface and this is the cause of the short fluorescence lifetimes and breaking off of the fluorescence. It is fortunate that the HSnCl excited state zero-point level is still fluorescent or it would not be detectable by LIF spectroscopy. Our calculations also predict that HSnBr should also fluoresce on excitation of low-lying bending levels in the excited state. |
Issue Date: | 23-Jun-20 |
Publisher: | International Symposium on Molecular Spectroscopy |
Citation Info: | APS |
Genre: | CONFERENCE PAPER/PRESENTATION |
Type: | Text |
Language: | English |
URI: | http://hdl.handle.net/2142/107689 |
Date Available in IDEALS: | 2020-06-26 |