Isolation and Thermal Reactions of the Intermediates from

13320

J. Phys. Chem. B 2004, 108, 13320-13328

Isolation and Thermal Reactions of the Intermediates from BrCH2CH2OH Decomposition on Cu(100) and Oxygen-Precovered Cu(100) Pei-Teng Chang, Jain-Jung Shih, Kuan-Hung Kuo, Chia-Yuan Chen, Tao-Wei Fu, Dong-Lin Shieh, Yung-Hsuan Liao, and Jong-Liang Lin* Department of Chemistry, National Cheng Kung UniVersity, Tainan, Taiwan, Republic of China ReceiVed: May 14, 2004; In Final Form: May 18, 2004

The reactions of BrCH2CH2OH were investigated on clean and oxygen-precovered Cu(100) surfaces under ultrahigh vacuum conditions. Reflection-absorption infrared spectroscopy (RAIRS) studies were performed to examine the surface intermediates that were generated from BrCH2CH2OH decomposition. Density functional theory calculations were employed to predict the infrared spectra, assisting in the identification of the reaction intermediates. On Cu(100), -CH2CH2O-, formed from the simultaneous scission of the bromine-carbon and oxygen-hydrogen bonds of BrCH2CH2OH at ∼190 K, decomposed and evolved into C2H4 between 210 and 310 K in temperature-programmed reaction/desorption (TPR/D) experiments. A small amount of CH3CHO desorption was also observed. On oxygen-precovered Cu(100), -CH2CH2O- was also generated at lower exposures (