Siam Quantum 1.2.15

Post date: May 1, 2020 4:53:43 AM

• • 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)