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<DIV>Yes, there are.The cohesive (lattice) energy is the energy that must be</DIV>
<DIV>added to the crystal to separate its component neutral atoms (ions) into</DIV>
<DIV>neutral free atoms (ions) at rest at infinite separation.</DIV>
<DIV>Chemical potential is defined as mu=G/N, where G=U-TS+PV, and N is the total</DIV>
<DIV>number of particles. At zero temperature (T=0) and constant volume (V=cte),</DIV>
<DIV>one can conclude that mu=U/N, where U as internal energy at such</DIV>
<DIV>circumstances is the total energy which can be calculated by wien2k code,</DIV>
<DIV>and N is the number of electrons. So obviously in the case of</DIV>
<DIV>mu=U/N,chemical potential should be equal to Fermi energy, that is mu=E_f.</DIV>
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<DIV>Does this mean that the chemical potential alway be negative? so does the
Fermi energy?</DIV>
<DIV>and i remember the defination of the chemical potential is :</DIV>
<DIV>mu=d(G)/d(N)</DIV>
<DIV>can this defination be treated as mu=U/N?so do in the WIEN2K?</DIV>
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<DIV>Now I think it is clear that cohesive (lattice) energy refers to the number</DIV>
<DIV>of atoms (ions), but chemical potential refers to the number of electrons.</DIV>
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<DIV>>> Hi,all wien2k users:</DIV>
<DIV>>>
I have a basic physical question. Are there difference between the</DIV>
<DIV>cohesive energy and chemical potential?</DIV>
<DIV>>> </DIV>
<DIV>>> Regards</DIV>
<DIV>>> </DIV>
<DIV>>> </DIV>
<DIV>>> </DIV>
<DIV>>> </DIV>
<DIV> </DIV>
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