Abstract
The structures and energetics of the mononuclear titanium carbonyls Ti(C4H3S)i(CO)j, (i+j=4, i=1,2,3,4, j=1,2,3,4) and binuclear titanium carbonyls with thiophene Ti2(C4H3S)m(CO)n (m=1, 2, 3, 4; n=1, 2, 3, 4; m+n=8) have been investigated using density functional theory. Every structure of the binuclear titanium carbonyls with thiophene is bridged by CO group or C4H3S group and sometimes dibridged by both CO group and C4H3S group. The energy required for the dissociation of Ti2(C4H3S)2(CO)6 into Ti(C4H3S)2(CO)2 and Ti (CO)4 fragments is 71.4 kcal/mol by the B3LYP method and 89.6 kcal/mol by the BP86 method respectively, which is higher than the energy for the dissociation of other Ti2(C4H3S)m(CO)n structure into Ti(C4H3S)i(CO)j fragments. All the binuclear titanium carbonyls with thiophene are unsaturated system and the electron configuration of the titanium atom of Ti2(C4H3S)2(CO)6 is 17-electron configuration, which is nearest to the 18- electron configuration.
