GAUSSIAN is a well known and widely used quantum chemical calculations software package. There are many prominent scientists, including some of those who originally wrote substantial parts of the program, who claim to be banned by Gaussian Inc. from ever using the software. However, in most cases the reality of the situation is that the scientist in question actually writes computer code for a competing company. As a result GAUSSIAN, Inc. has declined to provide the GAUSSIAN source code to these individuals. Instead, most of these scientists often use versions of GAUSSIAN that only include binary files. In this way, GAUSSIAN, Inc. has protected its property without preventing others from using the program. Moreover, creators of Gaussian point out that they publish their algorithms, making them part of the public domain and accessible to others.
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