COMPLETE SPACE QUANTUM CHEMISTRY BY MULTIRESOLUTION MULTIWAVELET BASIS SET

Abstract

Quantum chemistry program based on Multiresolution Multiwavelet (MRMW) basis set is much simpler and can be more efficient than the conventional one based on Gaussian basis set in molecular geometry optimization because the Hellmann Fynman Theorem (HFT) holds for the complete space which MRMW provides. It is numerically shown that large Gaussian basis sets can provide the chemical information with chemical accuracy for very small molecular systems despite the incompleteness of their basis set. However, even for the relatively small size molecule of CH4 , the error from the basis set incompleteness results in an error larger than an acceptable chemical accuracy. The advantage of the MRMW complete basis set in vibrational analysis is also discussed.