No. Although the last two terms (asymmetry and pairing) represent components that go beyond a pure classical model, the formula does not take in account shell effects. So for nuclei away from stability, you need models that consider shell effects / form isomers etc.
No. Although the last two terms (asymmetry and pairing) represent components that go beyond a pure classical model, the formula does not take in account shell effects. So for nuclei away from stability, you need models that consider shell effects / form isomers etc.
For completeness, one should maybe add that the formula also doesn't work well for nuclei with roughly A
See the attached link for a quick comparison between fitted data and experimental results.
http://talador.com.ar/jeremy/wasora/realbook/._realbook017.html
The Bethe-Weizsaecker semi-empirical mass formula is essentially based on the liquid drop model (LDM) of the nucleus where the surface is sharply defined, has a constant internal density and a latent heat of vapourization proportional to the density. The main contribution to the binding energy comes from the volume energy term arising from the short- range nature of nuclear forces leading to their saturation. The LDM is not valid for nuclei with very small mass number values below A =12 where the surfaces can be considered as diffuse. The LDM is a classical model. Quantum mechanical properties manifested in the asymmetry energy term, pairing and shell structure effects do not contribute much to the overall binding energy per nucleon. In this way the Bethe- Weizsaecker formula is capable of reproducing the gross properties of over 200 medium-heavy and heavy stable and unstable nuclei, particularly the energy released in nuclear fission.
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