State-selected imaging of HCCO radical photodissociation dynamics

Abstract

We present a dc sliced ion imaging study of HCCO radical photodissociation to CH and CO at 230 nm. The measurements were made using a two-color reduced Doppler probe strategy. The CO rotational distribution was consistent with a Boltzmann distribution at 3500 K. Using the dc slice ion imaging approach, we obtained CO images for various rotational levels of CO (v=0). The results are largely consistent with earlier work, albeit with a significant 0.9 eV peak seen previously in the translational energy distributions absent in our state-selected imaging study.

State-selected imaging studies of formic acid photodissociation dynamics

“…26,27 Briefly, a mo-lecular beam of HCOOH was prepared by bubbling He ͑around 1 atm pressure͒ through a liquid sample ͑Aldrich͒ and introduced into the source chamber via a pulsed valve ͑General Valve Series 9͒ with a 0.5 mm orifice. 26,27 Briefly, a mo-lecular beam of HCOOH was prepared by bubbling He ͑around 1 atm pressure͒ through a liquid sample ͑Aldrich͒ and introduced into the source chamber via a pulsed valve ͑General Valve Series 9͒ with a 0.5 mm orifice.…”

Quantum-chemical approach to serine formation in the interstellar medium: A possible reaction pathway

“…The product formed after this step is HCCO, detected in TMC−1 and Sgr B2 clouds (Turner & Sears 1989). HCCO is also an important intermediate in combustion chemistry and in the formation of other interstellar molecules (Huang et al 2008). Table 1.…”

Electronic Population Inversion in HCCO/DCCO Products from Hyperthermal Collisions of O(3P) with HCCH/DCCD

“…The detected DCCO products must survive long enough to be detected; therefore, they must be either in the ground state, with internal energies below the dissociation limit, or in the excited quartet state. Products in the B̃ 2 Π state would be expected to dissociate before reaching the detector through predissociation, as the fluorescence quantum yield from this state is 10 –4 ; therefore, only a small percentage of HCCO (B̃ 2 Π) products would undergo radiative relaxation and survive to be detected. ,, Nascent ground-state products with high internal energies will also dissociate. The fraction of nascent DCCO products that dissociate reaches ∼92% at E coll = 100.4 kcal mol –1 (see section 4 in the Supporting Information).…”