Do not run this as root. Create a dedicated user (e.g., gaussian ).
# Extract to /opt or /home tar -xjvf G16_AVX2.tbz -C /opt/ chmod -R 750 /opt/g16 The critical part: Environment Variables echo 'export g16root=/opt' >> ~/.bashrc echo 'export GAUSS_SCRDIR=/scratch/$USER' >> ~/.bashrc echo 'source /opt/g16/bsd/g16.profile' >> ~/.bashrc
cd /opt/g16 ln -sf g16_avx2 g16 Linux handles I/O differently than Windows. Gaussian’s algorithm relies heavily on reading/writing to disk. If you use a standard SATA SSD, your expensive CPU will spend 80% of its time waiting. Gaussian 16 Linux
This usually means your shell limits are too low. Linux has a hard limit on "Max user processes."
Here is your no-fluff guide to installing, optimizing, and debugging Gaussian 16 on a Linux environment (CentOS/RHEL/Ubuntu). Unlike modern software, Gaussian 16 doesn't come with a pretty ./configure script. It comes as a tarball (usually G16_AVX2.tbz ). The installation is essentially extraction and declaration . Do not run this as root
Yes, the learning curve for bash is steeper than clicking a .exe . But once you learn to chain jobs with ; , run background processes with & , and monitor htop , you will never go back.
%Chk=opt_freq.chk %Mem=32GB %NProcShared=16 %R2C=2 #p opt freq b3lyp/6-31g(d) int=ultrafine Title Linux has a hard limit on "Max user processes
ulimit -s unlimited ulimit -n 65536 ulimit -u unlimited Add these to your g16.sub script. If you are using ssh , you may need to edit /etc/security/limits.conf :
Whether you are setting up a local workstation (like an AMD Threadripper + 4090 build) or logging into a university HPC cluster, running G16 on Linux isn't just faster—it unlocks the full potential of the software.