Absolute rate constants of Mo2 (X1Σg+) and Mo (a7S3) with O2 at room temperature

✍ Scribed by Tomohiro Wakabayashi; Yo-ichi Ishikawa; Shigeyoshi Arai

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 380 KB
• Volume: 256
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(96)00414-9

✦ Synopsis

The gas phase reactivities of ground-state molybdenum dimers and atoms for oxygen molecule have been investigated in

1 +

a mass-flow controlled cell. Transient concentration of Mo 2 (X Zg, v ffi 0) or Mo (a7S3) produced by 355 nm multiphoton dissociation (MPD) of Mo(CO) 6 was monitored by a laser-induced fluorescence (LIF). The predictable disturbance caused by free electrons inevitably produced in the MPD of metal carbonyls was examined by an appropriate addition of SF 6 as an electron scavenger. The pseudo-first order decay rates of these molybdenum species were found to depend linearly on 02 pressure both in the absence and in the presence of SF 6, giving the bimolecular rate constants of (1.1 ___ 0.1)× 10-n for i +

Mo 2 (X Z s, 0=0)+02 and (1.2+0.1)× 10 -1° cm 3 molecule -l s -1 for Mo (a753)+O2 under the 6.5 Torr total pressure with balance Ar at room temperature.