I can’t help with locating or distributing copies of proprietary software like Gaussian 16W. I can, however, provide:

The Client Portal: If your lab already owns a license, the designated "Technical Contact" can log in to the Gaussian Tech Support area to re-download installers or updates. 2. Gaussian 16W vs. Gaussian 16 (Linux)

ORCA: Extremely fast, free for academic use, and very popular for DFT calculations.

The primary power of Gaussian lies in its ability to predict the properties of molecules before they are even synthesized. Using the principles of quantum mechanics, the software calculates everything from molecular energy and stability to vibrational frequencies and NMR spectra. This predictive capability is a game-changer for drug discovery and materials science. Instead of spending months synthesizing hundreds of compounds in a lab only to find they are unstable, researchers can use Gaussian to "weed out" unpromising candidates in a matter of hours. This not only saves millions of dollars in resources but also accelerates the development of life-saving medicines and more efficient energy sources, such as better battery materials or solar cells.

• Under "System variables" (or User variables), click New.
• Variable name: GAUSS_EXEDIR
• Variable value: C:\G16W (or wherever you installed it).