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按原子级别描述辉石类矿物—透辉石(CaMgSi_2O_6)结构的计算模型已有所发展。一维硅酸盐链状结构的最佳计算模型允许链上的所有键角和键长有所变化。该模型的晶体能是由库仑项、近邻斥力项、键角弯曲和键拉伸等各项加以计算的。当包括晶格参数在内的16个结构变量所示的能量达最小时,便获得一个能较好再现观测结果的结构。弹性常数也做了计算,它与实验结果很相符。在50千巴的模拟压力下对于该模型反复进行了计算,并获得弹性常数的压力导数。计算所得的晶格参数的压力导数、键长和键角与实验观测的大致吻合。对于硅酸根链有着更多的制约条件的其它两种计算模型不能满意地再现弹性常数。
A computational model describing the structure of the pyroxene-diopside (CaMgSi2O6) at the atomic level has been developed. The best computational model for a one-dimensional silicate chain structure allows all bond angles and bond lengths in the chain to vary. The crystal energy of the model is calculated by Coulomb term, neighbor repulsion term, bond angle bending and bond stretching. When the energy shown by the sixteen structural variables, including the lattice parameters, is minimized, a structure that reproduces the observations better is obtained. The elastic constant has also been calculated, which is in good agreement with the experimental results. The model was repeatedly calculated at a simulated pressure of 50 kPa and the pressure derivative of the elastic constant was obtained. The calculated pressure derivatives of the crystal lattice parameters, bond length and bond angle are roughly in agreement with the experimental observations. Two other computational models that have more constraints on silicate chains can not satisfactorily reproduce elastic constants.