Bethe-Weizsäcker Formula
B(Z,A) = a_v·A − a_s·A^(2/3)
− a_c·Z(Z−1)/A^(1/3)
− a_a·(A−2Z)²/A
+ δ(Z,A)
a_v = 15.75 MeV (volume)
a_s = 17.80 MeV (surface)
a_c = 0.711 MeV (Coulomb)
a_a = 23.70 MeV (asymmetry)
δ = ±11.2/A^(1/2) MeV (pairing)
+ even-even, − odd-odd