Q-Chem 4.1 Release Download

Last update 7/15/2013


Click here for Q-Chem 4.1.0 Manual (pdf file)

Click here for Q-Chem 4.1.0 release log

Click here for Q-Chem 4.1 installation guide

Q-Chem 4.1 Package Distribution

1. Please select the Q-Chem executable binary codes you wish to download:

Linux 64 Bit Parallel Code based on MPICH

Linux 64 Bit Serial/multicore-parallel Code

Linux 64 Bit Parallel Code for OpenMPI 1.7.3

IBM AIX 6.1 or above 64 Bit Parallel Code

Windows 32 Bit Parallel Code (Console Program)

Windows 32 Bit Serial/multicore-parallel Code (Console Program)

Mac Intel OSX 64 Bit Parallel Code (Existing MPICH2 installation is required)

Mac Intel OSX 64 Bit Serial/multicore-parallel Code

2. Please select a download type:

Standard download: for new and upgrade installations

(During installation please be sure to provide us with an accurate e-mail address when prompted for one. It is required so we can locate your account, and contact you should there be any problems with your license request.)


Two ways to install Q-Chem 4.1

1) download the standard distribution by selecting a package above and untar it.

tar xvf qc4101.tar

2) download the universal online installer (recommended) using wget.

wget -N http://www.q-chem.com/download/qcinstall/qcinstall.sh
chmod +x qcinstall.sh

Run the installer qcinstall.sh and follow the onscreen instruction


After a successful installation you need to wait to receive license file by email, and save it as


Q-Chem Package Update and Maintenance

a) to update the installed Q-Chem to the latest distribution, run


[Package maintenance utility qcupdate.sh is the new added feature in 4.1 release. To upgrade pre-4.1 Q-Chem installation please download and run standard installer qcinstall.sh. ]

b) to re-generate and sumit license data, run

$QC/qcinstall.sh --update-lic

c) to receive regular updates you can use Linux cron utility and add the line below as the cron command. Please consult your system administrator for questions about using cron.

$QC/qcupdate.sh > $QC/qcupdate.log

Q-Chem 4 Installation Guide and Step-By-Step Tutorials