critic2
About
critic2 is an open-source program for the topological analysis of scalar fields—most commonly the electron density—in both molecular and periodic (crystal) systems. It supports a wide range of quantum chemistry and plane-wave DFT codes as input sources.
Key capabilities include:
- Critical point search — bonds, rings, and cages from any scalar field.
- QTAIM integration — atomic charges, volumes, and multipole moments.
- Delocalization indices — from promolecular or DFT-level densities.
- NCI visualisation — reduced density gradient isosurfaces for non-covalent interaction analysis.
- Crystal structure analysis — symmetry, powder diffraction, intermolecular interaction energies.
Links
Citation
A. Otero-de-la-Roza, E. R. Johnson, V. Luaña, Comput. Phys. Commun. 185, 1007 (2014). A. Otero-de-la-Roza, M. A. Blanco, A. M. Pendás, V. Luaña, Comput. Phys. Commun. 180, 157 (2009).
Ángel Martín Pendás
Principal Investigator
Professor of Physical Chemistry at the University of Oviedo. Pioneer of orbital-invariant approaches to chemical bonding, including the Interacting Quantum Atoms (IQA) energy partition and topological electron population statistics.