Sent to CCL by: "John Simmie" [john.simmie%%nuigalway.ie] Try "Comprehensive Handbook of Chemical Bond Energies" by Yu-Ran Luo he gives Co-S as 331 kJ/mol based on a 1972 review by Smoes et al. in J Bull Sco Chim Belg 81, 45-56. John Simmie//john.simmie]-[nuigalway.ie//National University of Ireland, Galway