Intramolecular charge‐transfer excitation energies from range‐separated hybrid functionals using the Yukawa potential

Abstract

Abstract Valence and intramolecular charge‐transfer excitation energies of middle‐sized molecules are calculated by time‐dependent density functional theory, with the long‐range corrected hybrid functionals employing the recently developed range‐separation schemes using the Yukawa potential. The Yukawa potential allows modest mixings of the Hartree–Fock exchange over a wide range of electron–electron distance. The Yukawa variant of the Coulomb‐attenuated method (CAM) achieves comparable accuracy in using CAM‐B3LYP functional for predicting not only various types excitation energies but also atomization energies, retaining 100% of the exact exchange potential in large interelectron distances. It is demonstrated that the use of the Yukawa potential is advantageous over the conventional range‐separation schemes with the error function. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009