Quantum chemical calculations on the structure and electronic properties of TiC2

The geometry of TiC2 in its ground and low-lying excited electronic states has been determined via ab initio electronic structure methods with extended basis sets and using both single-reference and multireference techniques for treating electron correlation. The calculations yield a thermodynamically stable triangular C2v structure with a two-fold coordination of the C2 moiety to Ti exhibiting a 3B1 ground state. The linear Ti–C–C structure, with one-fold coordination is found to be a saddle point. The results obtained at the density functional (BP86 and B3LYP) levels for the lowest triplet state are in qualitative agreement with higher-level multireference calculations.