New Empirical Equation for Atomic Masses

A new empirical equation for atomic masses has been developed. This equation has been successfully applied to atomic masses of nuclides heavier than nickel. The form used is that of an expression for the mass defect, $\Delta M=M-A$, as a function of $Z$ and $A$: $\Delta M(A, Z)={\alpha }_0+{\alpha }_{1}A+{\alpha }_{2}Z+{\alpha }_{3}AZ+{\alpha }_4{Z}^2+{\alpha }_5{A}^2+\delta .$ Because of the effects of nuclear shell structure a different set of coefficients is necessary for the different nuclear shell regions.