Gaussian (software)

Gaussian (software)
Name	Gaussian
Developer	Gaussian, Inc.
Released	0 1970
Latest release version	Gaussian 16
Latest release date	2016
Programming language	Fortran
Operating system	Linux, Windows, macOS
Genre	Computational chemistry
License	Proprietary

Gaussian (software). Gaussian is a prominent suite of programs for computational chemistry, widely used for performing electronic structure calculations. First developed in the 1970s, it has become an industry standard for predicting the properties of molecules and reactions in fields ranging from pharmaceuticals to materials science. The software is developed and distributed by the privately held company Gaussian, Inc., founded by John Pople.

Overview

Gaussian is a comprehensive software package designed for performing sophisticated quantum chemistry calculations. It is employed by researchers in academia, government laboratories, and industry to model chemical systems and predict a vast array of molecular properties. The program's name originates from its use of Gaussian-type orbitals as basis functions, a mathematical choice that enhances computational efficiency. Its development has been closely tied to advancements in theoretical chemistry and computer hardware.

Features and capabilities

The software supports a wide range of computational methods, including foundational Hartree–Fock theory, advanced density functional theory (DFT), and highly accurate coupled cluster techniques. Key capabilities include calculating molecular geometries, vibrational frequencies, thermochemical data, and reaction pathways. It can also model properties such as NMR chemical shifts, polarizability, and excited states via time-dependent density functional theory. These features are essential for studies in catalysis, spectroscopy, and drug design.

Theoretical foundations

Gaussian's methodologies are built upon the principles of quantum mechanics, specifically the Schrödinger equation. It implements semi-empirical methods, ab initio methods, and various density functional theory functionals. The use of Gaussian functions to approximate atomic orbitals was pioneered by John Pople and is central to the program's algorithm, allowing for the efficient computation of complex integrals. This theoretical framework enables the prediction of electronic structure and energy for diverse chemical systems.

Input and output

Users interact with Gaussian via a plain-text input file that specifies the molecular system, calculation type, basis set, and method. A typical input includes a Z-matrix or Cartesian coordinates to define molecular geometry. The program generates detailed output files containing results such as total energy, optimized structures, and molecular orbitals. Important results are often visualized using third-party software like GaussView or Avogadro. The output is critical for analysis in publications for journals like The Journal of Chemical Physics.

Versions and history

The first version was created by John Pople and his research group at Carnegie Mellon University, with its roots in the program IBM 7090. Major releases include Gaussian 70, Gaussian 76, Gaussian 80, and the widely used Gaussian 92, Gaussian 98, and Gaussian 03. The current version, Gaussian 16, was released in 2016. Development shifted to the commercial entity Gaussian, Inc. in the late 1980s. Each version has incorporated new methodologies, such as those developed by Walter Kohn and Pople's work on computational models.

Applications

Gaussian is applied across numerous scientific disciplines. In pharmaceutical research, it aids in drug discovery by modeling enzyme interactions and ligand binding. In materials science, it helps design novel polymers, nanomaterials, and semiconductors. Environmental chemists use it to study atmospheric reactions and pollutant degradation. Its predictions are routinely compared with experimental data from techniques like infrared spectroscopy and mass spectrometry, making it indispensable in modern chemical research.

Category:Computational chemistry software Category:Proprietary software Category:Fortran software