OLEX: Getting started

Introduction

The software can import structural data via a number of crystallographicfile formats (SHELXL model files, CIF, MDL MOL), generate the extended structure if required, and produce a picture. Extended structures can be exported as MOL files and pictures as bitmaps and JPEG files. The OLEX graphical system is built on OpenGL® (Silicon Graphics). The Windows® implementation of OpenGL allows the use of up to eight uniform or directional light sources, different material properties and lighting models (which define ambient scene light intensity and how reflection angles have to be calculated). The OLEX background designer allows pictures to be superimposed on semi-transparent backgrounds and predefined or user programmable gradients. As OLEX has been designed for use with extended structures, the mouse-driven interface is an essential part of the program. The interface is flexible, giving the user a choice of how to carry out a particular operation. For example, almost all operations on structural elements can be performed using either screen selections or a list-based method.
Standard operations such as the measurement of interatomic distances, valence angles or dihedral angles are also supported, as is viewing along crystallographic directions. Additional facilities include atom labelling, adjustable atom and bond radii and the determination of the current view direction. Tools specifically related to the analysis of topology and short interactions are described in Topological Analysis section.