CAJ | 학술논문

X射线衍射实验显示固氩是面心立方( fcc)晶格结构,目前对晶体氩的研究只限于两体,三体以及四体相互作用势。本文利用多体展开方法和超分子单、双(三)重激发耦合簇理论(CCSD(T))对固氩fcc晶格结构的三体和四体的几何构型、几何参数、不同体积下所有三体和四体构型的势能以及各构型所占比例等几个方面进行了准确的量子化学计算。结果表明：所有三体构型中对总的三体势能贡献最大的是构型1、构型6、构型12和构型23；三体势及其交换部分和色散部分的计算结果与现有解析经验势在长程部分符合得非常好,但在短程部分有较小差异。所有的四体构形中对总的四体势能贡献最大的是构型1,构型2,构型4,构型5,构型7和构型8；四体势及其交换势部分和色散部分的计算结果尚无解析经验势可比较。利用这些特殊构型的相关数据并结合其它构型,可拟合出更准确的三体经验势函数及其参数,也为拟合四体经验势函数及其参数提供了重要的参考价值。
X사선연사실험현시고아시면심립방( fcc)정격결구,목전대정체아적연구지한우량체,삼체이급사체상호작용세。본문이용다체전개방법화초분자단、쌍(삼)중격발우합족이론(CCSD(T))대고아fcc정격결구적삼체화사체적궤하구형、궤하삼수、불동체적하소유삼체화사체구형적세능이급각구형소점비례등궤개방면진행료준학적양자화학계산。결과표명：소유삼체구형중대총적삼체세능공헌최대적시구형1、구형6、구형12화구형23；삼체세급기교환부분화색산부분적계산결과여현유해석경험세재장정부분부합득비상호,단재단정부분유교소차이。소유적사체구형중대총적사체세능공헌최대적시구형1,구형2,구형4,구형5,구형7화구형8；사체세급기교환세부분화색산부분적계산결과상무해석경험세가비교。이용저사특수구형적상관수거병결합기타구형,가의합출경준학적삼체경험세함수급기삼수,야위의합사체경험세함수급기삼수제공료중요적삼고개치。
X-ray diffraction experiments shows that solid argon is a face-centered cubic crystal structure ( fcc structure). At present, crystal argon is studied involving two-, three- and four-body potentials. Using the many-body expansion method and the double cluster with full single and double excitations plus perturbative treatment of triples ( CCSD( T) ) , the properties of fcc structure for solid argon which include geometrical config-uration, geometrical parameters, potential energy of three- and four-body potentials and the proportion of all configurations at different volumes were accurately calculated. It is concluded that the configuration 1 , 6 , 12 and 23 play most important role in all three-body potential configurations. The calculation results of three-body po-tential, exchange potential and dispersion potential are in good agreement with the analytic experience potential in long-range part, but have small differences in short-range part. The configuration 1, 2, 4, 5, 7 and 8 play very important role in all four-body potential configurations, and there is not analytic experience potential to compare between the calculated results of four-body potential, exchange potential and dispersion potential. U-sing the data of these special configurations in combination with other configurations can fit a more accurate three-body experience potential function and its parameters, and also provide important reference value about fit four-body experience potential function and its parameters.