Rotationally Resolved Rate Constant Measurements for Removal of CH(A2Δ and B2∑−) by Ketene. Issue 4 (1994)

• Record Type: Journal Article
• Authors: Luque, Jorge; Ruiz, Javier; Martin, Margarita
• Is Part Of: Laser chemistry. Volume 14:Issue 4(1994)
• Page Start: 207
• Page End: 216
• Publication Date: 1994
• Subjects: Methylidine -- Quenching -- Excited States; Lasers in chemistry -- Periodicals; 542.8
• DOI: 10.1155/1994/79483
• Languages: English
• ISSNs: 0278-6273

Abstract

Abstract : Rate constants for total removal of CH(A 2 Δ ) and CH(B 2 ∑ − ) in collisions with ketene were measured. For theA 2 Δ state, rate constants increased with vibrational quantum number; measured values were (4.5 ± 0.5) × 10 -10 cm 3 molec -1 s -1 and (8.0 ± 1) × 10 -01 cm 3 molec -1 s -1 for v′ = 0 and v′ = 2 respectively. For v′ = 0, rotational levels with quantum numbers from N′ = 4 to N′ = 16 were removed with similar rates within experimental errors; collisional disappearance of levels with higher rotational quantum numbers was faster for a factor of about 1.4. Calculations of cross sections for ketene and other fast colliders, assuming a multipole model, obtained a qualitative correlation with experimental values. CH(B 2 ∑ − ) was more efficiently removed than CH(A 2 Δ, v′ = 0); for the lowest rotational levels a rate constant of (5.8 ± 0.3) × 10 -10 cm 3 molec -1 s -1 was measured and a moderate increase with rotational quantum number was observed.