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。其一是开发用于在个人计算机上计算晶体结构的图形程序，例如NEC 98001系列的计算机。该程序必须适用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，特别是斜长石族矿物。在指定期间内取得的成果摘要如下：1.程序Crystal是由M.Hirano用n88BASIC编写的MS-DOS版本。新的改进版本，标记为水晶18，具有原始程序中没有的各种功能。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。建立了斜长岩Pb5Sb8s17&gt；的亚结构-超结构的合理关系，导出了它们的晶轴之间的变换矩阵。对闪锌矿结构的进一步研究，充分阐明了斜长石群的细胞孪生机制。本研究的结果将对促进硫酸盐的系统学乃至矿物和无机材料的结构研究有很大的贡献。

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.