Abstract
The equivalent potential of water for the electronic structure of threonine (Thr) in solution is constructed by the first-principles, all-electrons, ab initio calculations. The main process of calculation consists of three steps. First, the geometric structure of the cluster containing Thr and water molecules is calculated by the free cluster calculation. Then, based on the obtained geometric structure, the electronic structure of Thr with the potential of water molecules is calculated using the self-consistent cluster-embedding method. Finally, the electronic structure of Thr with the potential of dipoles is calculated. The results show that the major effect of water on the electronic structure of Thr is to raise the occupied molecular orbitals near the Fermi level by about 0.01 Ry on average, and its energy gap is almost not changed. The effect of water on the electronic structure of Thr can be simulated by dipoles potential.
Acknowledgements
This work was supported by the National Natural Science Foundation of China (Grant No: 30470410). The work was also supported by Shanghai Supercomputer Center. The calculations were performed on the super computer DAWN 4000A of Shanghai Supercomputer Center of China.