### Electronic molecular descriptors determining/regulating the long-range molecular interactions

#### Average Quasi Valence Number (AQVN)

Z* = Σn_{i}(Z_{i}-Z_{0})/N

Z* is the average quasi-valence number (AQVN), Z_{i} is the atomic number of the i-th element in a molecule, Z_{0} is the atomic number of inert-elements that precedes the element Z_{i} (e.g. for C, N, O it is He, for P and S it is Ne), and N is the total number of atoms in a molecule.

#### Electron-Ion Interaction Potential (EIIP)

EIIP = Z* sin(3.267 Z*)/25

The argument of the sine function is in radians, and EIIP is given in Rydberg (Ry).

Electronic molecular descriptors AQVN and EIIP are derived from the General Model Pseudopotential [1,2]

**References**

- Veljkovic V, Slavic I (1972) Simple general-model pseudopotential. Phys Rev Lett 29: 105-106.
- Veljkovic V (1973) The dependence of the Fermi energy on the atomic number. Phys Lett 45A: 41-42.