Post date: May 1, 2020 4:53:43 AM
is a major feature enhancement release
Try our new option -HESSIAN. For example,
To compute vibration information at current geometry:
SQ.EXE h2o.xyz 321g.txt -HESSIAN
However, theoretical vibration frequencies are defined at equilibrium geometry; so you need to make sure that the input geometry has been optimized at the same level of theory (method/basis set). The following run will do both the optimization and the vibration analysis:
SQ.EXE h2o.xyz 321g.txt -OPT -HESSIAN
Also, check out our newly published paper:
T. Chachiyo and H. Chachiyo “Understanding electron correlation energy through density functional theory” Computational and Theoretical Chemistry 1172 (2020) 112669. https://doi.org/10.1016/j.comptc.2019.112669
T. Chachiyo and H. Chachiyo “Simple and accurate exchange energy for density function theory” Molecules 25 (2020) 3485. https://doi.org/10.3390/molecules25153485
VWN5 parameters can be changed. See helps on the option -LDA for details. (run SQ.exe without argument to see helps)
Geometry optimization now print out "Optimized geometry" at the end along with distance matrix.
Cutoff threshold for geometry optimization is now strict to make sure it is really the equilibrium otherwise it will affects vibration analysis run.
Please cite this work as:
T. Chachiyo et al. (2016) "Siam Quantum: a compact open-source quantum simulation software for molecules," Thailand. see https://sites.google.com/site/siamquantum.
Get it now
Source code [Download]
Executables
Windows [Download] compiled with MinGW, lapack-3.10.0, and libxc-5.2.2 (using cmake)
Linux [Download] compiled with Ubuntu 22.04 LTS Desktop AMD-64, gcc 11.3.0, lapack-3.11.0, and libxc-5.2.3 (using cmake)
MacOS [Download] compiled with macOS 13.1 iMac M1, homebrew gcc 12.2.0, lapack-3.10.0, and libxc-5.2.3 (using cmake)
Basis Set (using GAMESS-US format)