Hunter College & the PhD Program of the Graduate Center, City University of New York, New York.
Department of Chemistry and Physics, Mount Saint Vincent University, Halifax, Nova Scotia, B3M 2J6, Canada.
J Comput Chem. 2018 Jun 30;39(17):1021-1028. doi: 10.1002/jcc.25102. Epub 2017 Nov 14.
Extraction of the complete quantum mechanics from X-ray scattering data is the ultimate goal of quantum crystallography. This article delivers a perspective for that possibility. It is desirable to have a method for the conversion of X-ray diffraction data into an electron density that reflects the antisymmetry of an N-electron wave function. A formalism for this was developed early on for the determination of a constrained idempotent one-body density matrix. The formalism ensures pure-state N-representability in the single determinant sense. Applications to crystals show that quantum mechanical density matrices of large molecules can be extracted from X-ray scattering data by implementing a fragmentation method termed the kernel energy method (KEM). It is shown how KEM can be used within the context of quantum crystallography to derive quantum mechanical properties of biological molecules (with low data-to-parameters ratio). © 2017 Wiley Periodicals, Inc.
从 X 射线散射数据中提取完整的量子力学是量子晶体学的最终目标。本文为此提供了一种可能的视角。人们希望有一种方法可以将 X 射线衍射数据转换为反映 N 电子波函数反对称性的电子密度。为此，早期为确定约束幂等单体重叠密度矩阵开发了一种形式体系。该形式体系确保了单行列式意义上的纯态 N 可表示性。晶体的应用表明，通过实施一种称为核能方法（KEM）的碎片方法，可以从 X 射线散射数据中提取大分子的量子力学密度矩阵。本文展示了如何在量子晶体学的背景下使用 KEM 来推导生物分子的量子力学性质（数据与参数比低）。© 2017 年威利父子公司
