Abstract: The new concept of the bound state model of the elements of first period, including hydrogen-like alkali metals, is proposed on the basis of some experimental results of“cold fusion”. It is necessary that the nuclei motions are taken into account, instead of Born-Oppenheimer approximation, for multimer problems such as(p,e,p)(D⁺,e,D⁺).The energy of the bound state is estimated in quantum machanics.The“excess heat of cold fusion”comes mainly from the energy of X-ray radiation,since X-ray emission rate is about 10⁴～10⁶ times of nuclear-fusion rate,and the ratio of the X-ray energy to the fusion energy is about 10²～10⁴. Basing on the bound state concept,a new form of matter structure appears,which is different from nucleus,atom,and molecule structures.The experimental evidences of the bound state concept are discussed and a new design of experiment is proposed.