UV photodissociation of η5-C5H5NiNO: an excited-state Jahn-Teller distortion produces a cartwheeling NO.
The 225 nm photodissociation of cyclopentadienylnickel nitrosyl was studied using velocity-mapped ion imaging with 1 + 1' REMPI detection of the NO (X (2)Π(1/2,3/2), v'' = 0) photofragment. The product recoil energy and angular distributions were measured for selected rotational states of NO. The NO product displays two speeds, a slow product peaked at the center of the ion image and a fast anisotropic product that has an inverted rotational population. In rotational states above J'' = 40.5, an even faster anisotropic NO photofragment appears, most likely because the metal-containing dissociation partner emerges in a lower electronic state, increasing the available energy. The μ-v-j vector correlations were measured and are consistent with the orientation μ∥v⊥ j. The observed vector correlations arise from an excited-state Jahn-Teller distortion of the parent, a distortion that bends the Ni-NO coordinate prior to dissociation.
Peden
Amber L
AL
Department of Chemistry, Kalamazoo College, 1200 Academy Street, Kalamazoo, Michigan 49006, USA.
Kieda
Ryan D
RD
Breck
Kelsey A
KA
Basore
Joseph R
JR
Kent
Caleb A
CA
Bartz
Jeffrey A
JA
D003517:Cyclopentanes / Q000737:chemistry; D005454:Fluorescence Polarization; D007834:Lasers; D013058:Mass Spectrometry / Q000295:instrumentation / Q000379:methods; D008956:Models, Chemical; D008968:Molecular Conformation; D009532:Nickel / Q000737:chemistry*; D009569:Nitric Oxide / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D010777:Photochemistry; D014466:Ultraviolet Rays
D003517:Cyclopentanes; D009942:Organometallic Compounds; D009569:Nitric Oxide; D009532:Nickel