Ab Initio Calculation of Equivalent Potential of Water for Electronic Structure of Valine

Abstract:

The equivalent potential of water for the electronic structure of valine (Val) was constructed on the basis of the first principles, all electron, ab initio calculations. The process involved three steps. First, a search for the minimum energy configuration of the system Val+7H2O was carried out by free cluster calculation. Then, the electronic structure of valine with the potential of water molecules was calculated with the self consistent cluster embedding (SCCE) method. Finally, the effect of water was simulated on valine by dipoles. Results show that the major effect of water on the electronic structure of valine is to raise the eigenvalues of eight orbitals under Fermi surface by about 0.775 5 eV on average. The effect of water on the electronic structure of valine can be well simulated by dipoles. The equivalent potential obtained can be applied directly to the calculation of the electronic structures of proteins in solution.