screening constant

Updated values of screening constants were provided by Clementi et al.

Note that the effective nuclear charge is calculated by subtracting the screening constant from the atomic number, 26.

The screening constant, and subsequently the shielded (or effective) nuclear charge for each electron is deduced as:

A calculation of the screening constant for a series of 16 sp and sp2 carbons gives an average precision of 5 ppm for the 13C nuclei.

Revised values of screening constants based on computations of atomic structure by the Hartree-Fock method were obtained by Enrico Clementi et al in the 1960s.

The final results expressed through the overlap integrals of STOs with the same screening constants are valid for the arbitrary parameters of STOs and potentials.

Clementi E & Raimondi DL 1963, Atomic Screening Constants from SCF Functions, Journal of Chemical Physics, vol.