Spectroscopy of small hydrocarbon radicals: A study of the vinyl, allyl, and methyl systems
This thesis focuses on the study of small hydrocarbon radical systems. Radicals are produced by pyrolysis of organic precursors that were engineered to decompose into desired products. The thesis is comprised of three complete studies. The first study analyzes a photo-electron spectrum of the vinyl radical. Vinyl is a particularly unstable molecule and therefore few previous studies have been published. An ionization potential of 8.25 [+-] [sup 0.2][sub 0.05] eV is derived from the spectrum and using this value [Delta]H[sup 0][sub f,0][C[sub 2]H[sub 3][sup +]] [le] 265.9 kcal/mol is obtained. the second study analyzes a rotationally resolved resonant enhanced 1 + 1 multiphoton ionization (REMPI) spectrum of the allyl radical in the region of 234 to 250 nm. By simulation of the vibronic bands most of the structure is assigned to three closely spaced electronic bands. One of the electronic states is believed to be perturbed by a pseudo-Jahn-Teller distortion. The final study analyzes a pulsed-field-ionization zero-kinetic-energy (PFI-ZEKE) spectrum of the methyl radical. It is the first PFI-ZEKE spectrum of a rotationally resolved polyatomic hydrocarbon radical. A simulation of the spectrum helps in assigning the rotational structure of a parallel type band. Several anomalous peaks are likely due to autoionization.
- Research Organization:
- Harvard Univ., Cambridge, MA (United States)
- OSTI ID:
- 6961260
- Resource Relation:
- Other Information: Thesis (Ph.D.)
- Country of Publication:
- United States
- Language:
- English
Similar Records
A laser spectroscopic study of the excited states and dynamics of AlH, HCl, NO[sub 2], C[sub 2]H[sub 2] and CH[sub 3]I
Electronic spectrum of allyl and allyl-d[sub 5] radicals. The B[1[sup 2]A[sub 1]] [l arrow] X[1[sup 2]A[sub 2]], C[2[sup 2]B[sub 1]] [l arrow] X[1[sup 2]A[sub 2]], and D[1[sup 2]B[sub 2]] [l arrow] X[1[sup 2]A[sub 2]] band systems