A program for the calculation of structural descriptors
by D. Svozil and H. Lohninger

TOPIX is a program for the calculation of structural descriptors. TOPIX runs on IBM PCs under Windows 95, or Windows/NT. TOPIX calculates about 130 topological and structural descriptors, which can be selected individually. A survey of types of descriptors is given below:

simple descriptors
  • molecular weight
  • counts of atom types (C, O, N, S, P, halogens)
  • bond counts (single, double, triple, and aromatic)
  • number of branches in moelcule
  • number of rings in molecule
topological descriptors
  • Randic indices [0..9]
  • modified Randic index
  • Randic information indices [0..9]
  • Kier [0..8]
  • Kier information indices [0..8]
  • Randic cluster index [3,4]
  • Randic cluster path index [30..39]
  • Kier cluster indices [3..4]
  • Kier cluster path indices [30..39]
  • Xu indices [1..3]
  • TopoJ
  • topological radius and diameter
  • Wiener index
  • Dimension
  • Bertz
  • IxAtCompMean, IxAtCompTot
  • Zagreb index [1..2]
  • Quadr
  • Schultz
  • Kappa [1...3]
  • Wiener distance
  • Wiener information index
  • DistEqMean, DistEqTot
  • MagnitDistTot
  • Polarity
  • Gordon
descriptors of substructures
  • augmented atoms

TOPIX can read structural data (connection tables) from either MOL format, or TRANSPEC format files. Click here to have a look at a screen shot of the user interface. A demo version of TOPIX, which is slightly restricted in it's usage, can be downloaded by clicking on the file name below. TOPIX comes with a help file and several sample structures.

  • Download the demo version of TOPIX - file TOPIXDEM.ZIP (approx. 1065 kBytes)

The full version of TOPIX is available directly from the authors for Euro 249 (Euro 99 for students and faculty members). Eastern European users, please contact D. Svozil (Prague, CZ). All others should contact H. Lohninger (Vienna, AT).