Downloadable software that serves as an application programming interface to permit third parties to create programs for customization and control of atomistic simulation software; providing software libraries; providing software libraries that include general storage, access and manipulation of numeric data for other applications, namely applications requiring high numerical precision and high speed of access; providing software libraries that use data storage and manipulation to provide data structures, storage and manipulation of data specific to computational chemistry models and calculations; providing software libraries that facilitate interoperation of distinct software packages and environments; providing software libraries that facilitate interoperation of distinct software packages and environments for five general purposes: automation, post-processing, integration, experimentation, and teaching; providing software libraries that allow use of multiple programming and scripting languages for interoperability while retaining binary storage for data and retaining precision floating-point values.