| Abstract: | The mechanism for the reaction of HCO with HNO has been studied at the G2M level of theory, based on the geometric parameters optimized by the BH&HLYP/6‐311G(d, p) method. There are three direct hydrogen abstraction channels producing (1) H2CO + NO, (2) H2NO + CO, and (3) HNOH + CO with barriers of 3.7, 3.9, and 10.4 kcal/mol, respectively. Another important reaction channel, (4), involves an association process forming HN(O)CHO (LM1) with a very small barrier and the subsequent isomerization and decomposition of LM1 producing HNOH + CO as major products. The rate constants of the dominant reaction channels (1), (2), and (4) in the temperature range 200–3000 K have been predicted by the microcanonical RRKM and transition state theory calculations with Eckart tunneling corrections. The theoretical result shows that in the high temperature range ( T > 1500 K), k1 (H2CO + NO) and k2(H2NO + CO) are preponderant, while in the low temperature range, both k4(LM1) and k4(HNOH + CO) appear to be dominant at high and low pressures, respectively. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36: 205–215, 2004 |
