It is an encrypted zip file. Not a password protected website. Not a rar. I downloaded it and ran file on it. Oddly the filename is .tar.

    $ file .reaxys.tar 
    .reaxys.tar: Zip archive data, at least v2.0 to extract

As one of the other top level comments said, the links to it are here: https://twitter.com/MichaelSLaufer/status/102263726560276889...