One of the difficulties to understand the properties of bulk water is exploring the structure and energy of water clusters.High-level ab initio calculations, such as MP2 and CCSD methods,can predict the accurate energy of water clusters but are difficult to be applied for the large molecules since it requires much CPU source and hard disks.It is more difficult to obtain the basis set limit of the conventional MP2 and CCSD correlation energies due to the inaccurate description of short-range correlation in wave function [1].