TopChem is specifically designed for the topological analysis of one-electron density functions. The program makes use of a full numerical algorithm enabling to numerically assign the data points of three-dimensional grids to basin volumes.

by J. Pilmé, Laboratoire de Chimie Théorique.

1 - Required Input :

  • Cube Grids (ELF, electron density, ..) or wfn gaussian file.

2 - Calculated integrated properties:

  • Basin Populations
  • Electrostatic Moments (local basins polarizations)
  • Molecular dipole

3 - References:

An introductory paper on TopChem, see:

New Insights in Quantum Chemical Topology Studies Using Numerical Grid-based Analyses. D. Kozlowski and J. Pilmé , J. Comput. Chem. Volume 32, Issue 15, pages 3207–3217, 2011

4 - Download

I will adhere the following conditions upon receipt of the code:
  • I understand that copyright and intellectual property rights are retained by the author
  • I am allowed to supply a copy of the code to anyone. in this case I will inform the author.
  • I will inform the authors of any substantial improving modification of the code
  • I agree to use this sotware for no profit purpose
  • I will not incorporate any part of the code in a commercial software

- Download  TopChem current version (3.0, LAST UPDATED ON JULY 2013): Accept

Examples obtained with TopChem (Isosurfaces displayed with Molekel4.3)

ELF localization domains (ELF = 0.85) of the zwitterionic glycine embedded in 50 water molecules.


Localization domains of ELF, L(r) and MESP for the water molecule.


ELF localization domains (ELF = 0.85) of benzene and diamond crystal (VASP grids)

Last updated on december, 2013.