Orac (MD program)

This article is about a molecular dynamics program. For more meanings of the word Orac, see ORAC.

In computer software, Orac is a classical molecular dynamics program, to simulate complex molecular systems at the atomistic level. In 1989-1990, the code was written originally by Massimo Marchi during his stay at International Business Machines (IBM), Kingston (USA). In 1995, the code was developed further at the Centre européen de calcul atomique et moléculaire (CECAM). It is written in the programming language Fortran. In 1997, it was released under a GNU General Public License (GPL).^[1] The latest release ^[2] of Orac may be run in parallel using the standard Message Passing Interface (MPI) libraries, allowing replica exchange simulations, multiple walkers metadynamics^[3] simulations and multiple steered molecular dynamics^[4] nonequilibrium trajectories.

Orac

Original author(s)	Massimo Marchi, Piero Procacci
Developer(s)	CEA, Saclay, Paris, FR; Florence University, IT
Initial release	1990; 35 years ago (1990)
Stable release	5.4.1 / 2010; 15 years ago (2010)
Preview release	6.0 / 2016; 9 years ago (2016)
Written in	Fortran
Operating system	Unix, Linux
Platform	IA-32, x86-64, NUMA
Available in	English
Type	Molecular dynamics
License	GPL
Website	www.chim.unifi.it/orac

See also

• Free and open-source software portal

• Comparison of software for molecular mechanics modeling