This quantity, which can be calculated using Slater's rules, arises due to the screening effect of inner-shell electrons, meaning the charges of protons in the nucleus appear weaker to an upper-shell electron.
Spiers formula uses an exponent of 2.94 in order to find this value, and for a compound it can be found by taking the 2.94th power mean of a particular series. The energy of the spin-orbit coupling increases as the fourth power of this value, which was calculated using a self-consistent field method by Clementi and Raimondi. Another set of methods adds either 1, 0.85 or 0.35 to a constant denoted sigma, and Clarence Zener calculated it using a variational principle. This quantity, which can be calculated using Slater's rules, arises due to the screening effect of inner-shell electrons, meaning the charges of protons in the nucleus appear weaker to an upper-shell electron. For 10 points, name this quantity which is always less than the atomic number, symbolized Z sub e-f-f
Spiers formula uses an exponent of 2.94 in order to find this value, and for a compound it can be found by taking the 2.94th power mean of a particular series.
Z_eff or Effective nuclear charge or Effective atomic number (prompt on partial)