The study of complex mineral and inorganic structures by means of computer graphics

这个项目可以分为两个主要部分。一个是开发一个图形程序，用于计算个人计算机（如NEC 98001系列计算机）上的晶体结构。该程序必须适合于研究矿物和无机晶体结构。另一种是应用该程序研究非常复杂的矿物结构，特别是斜长石矿物群。在指定期间取得的结果摘要如下1。由平野先生用n88BASIC编写的CRYSTAL程序被制成了一个MS-DOS版本。新的改进版本，称为CRYSTAL 18，具有原始程序中不可用的各种功能。增加的一些主要功能是：(1)可以制作和显示给定结构的任何薄片；(2)可以同时显示具有一系列不同方向的四个图。斜长石：Pb_5Sb_8S_<17>；导出了它们的结晶轴集的变换矩阵。进一步扩展到复长石结构的研究，充分阐明了整个复长石群的细胞孪生机制。例如，本研究取得的结果将对促进磺胺盐的分类学以及一般地对矿物和无机材料的结构研究作出相当大的贡献。

This project may be divided into two major parts. One is to develope a graphic program for calculating crystal structures on personal computers, such as those of the NEC 98001 series. The program must be suited for studying mineral and inorganic crystal structures. The other is to apply the program to study very complex mineral structures, specifically the plagionite group of minerals. The results obtained in the assigned period are summarized below.1. A MS-DOS version was made of the program CRYSTAL which had been written by M. Hirano with n88BASIC. The new improved version, denoted CRYSTAL 18, has various functions which are not available in the original program. Some of the major functions added are: (1) any thin slice of a given structure can be made and displayed and (2) four diagrams having a series of different orientations can be displayed simultaneously.2. The substructure-superstructure rational relationship has been established for plagionite, Pb_5Sb_8S_<17>; the transformation matrix has been derived to relate their sets of crystallographic axes. Further study extended to the fuloppite structure has fully elucidated the mechanism of cell-twinning underlying the whole plagionite group.The results achieved by the present stusy would provide, for example, considerable contribution to the promotion of the systematics of sulfosalts and in general to that of the structural study of minerals and inorganic materials.