New range-separated hybrids based on the TCA density functional

We have applied the Hirao and coworkers' range-separation procedure to the recently proposed (GGA-like) TCA functional and to the global hybrid obtained from it by using the theoretical mixing coefficient a(0) = 0.25. The range-separation parameter omega has been determined by optimizing the performances for some commonly used benchmark databases. Successively, we have applied the resulting functionals to the calculation of some vertical excitation energies. We have found that the range-separation procedure strongly improves the performances of both the TCA functional and its global hybrid. The results are better than those obtained by the corresponding range-separated hybrids based on the PBE functional. (C) 2011 Elsevier B.V. All rights reserved.