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采用分子力学方法计算了与ＡｌＰＯ_４－５分子筛相关的６４种设计结构的空间能．计算得到的空间能与其骨架拓扑结构间密切相关．正交ＡｌＰＯ_４－５００的空间能最低（－３４４７ｋＪ／ｍｏｌ），意味着该结构是最稳定的．它的结构与六方ＡｌＰＯ_４－５具有相同的骨架结构，另有两个设计的正交结构分子筛ＡｌＰＯ_４－５６２和ＡｌＰＯ_４－５５７的空间能较低，分别为－３４１９和－３４１８ｋＪ／ｍｏｌ，表明这两种结构是稳定的，并有可能被合成出来．发现空间能与结构中的层间氧桥“向上”或“向下”连接的有序性有关．因此，空间能可以作为设计的分子筛骨架存在的可能性大小的判据．
The molecular energies of 64 kinds of designed structures related to AlPO 4 -5 zeolite were calculated by molecular mechanics method. The calculated space can be closely related to its skeleton topology. Orthogonal AlPO 4-500 has the lowest space available (-3447 kJ / mol), which means the structure is the most stable. Its structure has the same framework structure as that of hexagonal AlPO_4-5, and the other two designed orthorhombic molecular sieves AlPO_4-562 and AlPO_4-557 have lower space energy of -3419 and -3418 kJ / mol, respectively, indicating that these two The structure is stable and may be synthesized. It was found that space can be related to the orderliness of the “up” or “down” connections of the interlayer oxygen bridges in the structure. Therefore, space can be used as a criterion for the size of the molecular sieve skeletons that are designed to exist.