This is another equation to calculate electronegativity but using a different method created by two men whose surnames were Allred and Rochow, hence these electronegitivities are given the label of Allred-Rochow electronegativites. This method considers how effective nuclear charge(Zeff and the covalent radius(r2cov) plus some constants to calculate electronegativity.
This is mulliken's equation to calculate electronegitivity. Mulliken uses ionisation energy and electron affinity, to calculate the relative tendancy of an atom to recieve or donate electrons.
This equation is used to calculate dipole moments from the dipole moment of the bond being considered ie C-Cl= meu bond and considers the angle between these C-Cl bonds to calculate the overall dipole moment of the whole molecule
This equation can be rearranged to calculate optical density(log10 I0/I), the extinction coefficient(epsilon), path length(l) and concentration (mol-1dm3). Usually it is used to calculate the extinction coefficient from organic experimental data.