Photoelectron spectroscopy of boron-containing reactive intermediates using synchrotron radiation: BH2, BH, and BF. Issue 3 (19th December 2019)

• Record Type: Journal Article
• Authors: Mukhopadhyay, D. P.; Schleier, D.; Fischer, I.; Loison, J.-C.; Alcaraz, C.; Garcia, G. A.
• Is Part Of: Physical chemistry chemical physics. Volume 22:Issue 3(2019)
• Page Start: 1027
• Page End: 1034
• Publication Date: 2019-12-19
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c9cp06010c
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : Mass selected slow photoelectron spectra (SPES) of three boron-containing reactive species, BH2, BH, and BF were recorded by double imaging photoion–photoelectron coincidence spectroscopy (i 2 PEPICO) using synchrotron radiation. Abstract : Mass selected slow photoelectron spectra (SPES) of three boron-containing reactive species, BH2, BH, and BF were recorded by double imaging photoion–photoelectron coincidence spectroscopy (i 2 PEPICO) using synchrotron radiation. All species were generated in a flow reactor from the H-abstraction of B2 H6 by F atoms created in a F2 microwave discharge. The spectrum of BH2 + exhibits a long bending mode progression with a 970 cm −1 spacing due to the large geometry change from bent to linear upon ionization. Its ionization energy was determined as 8.12 ± 0.02 eV. For BH, photoionisation from both X 1 Σ + singlet and a 3 Π triplet state was observed, permitting the experimental determination of the singlet/triplet gap (Δ E ST ) from the observed IE's of 9.82 eV and 8.48 eV. In addition, a threshold photoelectron spectrum of BF was recorded, which leads to an IE of 11.11 eV and an improved value for ν BF + of 1690 cm −1 . All spectra were simulated by calculating Franck–Condon factors from optimised structures based on quantum chemical calculations.