The potential energy surface of the reaction of F atom with .CH~2OH is studied by ab initio MO method. The structure parameters, vibration frequencies and energy of each stationary point on its potential energy surface are given. G2(MP2, SVP) method is applied in the calculations. Results show that: firstly, the proton on the oxygen migrates to the carbon forming a methyl group and the methyl group rotates, then one of its protons binds to the fluorine, thereby leading to the formation of HF and CH~2O. The calculated exothermic energy (455.9kJ.mol^-^1) agrees with the experiment result (439kJ. mol^-^1). In addition, a possible explanation for the absence of CHOH in the products, which was previously observed using IR spectroscopy, is given.

Key words: FLUORINE, AB INITIO CALCULATION, POTENTIAL ENERGY SURFACES, INFRARED SPECTROPHOTOMETRY