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Key Equations

Electrostatic energy for equilibrium separation distance between atoms Ucoul=ke2r0Ucoul=ke2r0
Energy change associated with ionic bonding Uform=Etransfer+Ucoul+UexUform=Etransfer+Ucoul+Uex
Critical magnetic field of a superconductor Bc(T)=Bc(0)[1(TTc)2]Bc(T)=Bc(0)[1(TTc)2]
Rotational energy of a diatomic molecule Er=l(l+1)22IEr=l(l+1)22I
Characteristic rotational energy of a molecule E0r=22IE0r=22I
Potential energy associated with the exclusion principle Uex=ArnUex=Arn
Dissociation energy of a solid Udiss=αke2r0(11n)Udiss=αke2r0(11n)
Moment of inertia of a diatomic molecule with reduced mass μμ I=μr02I=μr02
Electron energy in a metal E=π222mL2(n12+n22+n32)E=π222mL2(n12+n22+n32)
Electron density of states of a metal g(E)=πV2(8meh2)3/2E1/2g(E)=πV2(8meh2)3/2E1/2
Fermi energy EF=h28me(3NπV)2/3EF=h28me(3NπV)2/3
Fermi temperature TF=EFkBTF=EFkB
Hall effect VH=uBwVH=uBw
Current versus bias voltage across p-n junction Inet=I0(eeVb/kBT1)Inet=I0(eeVb/kBT1)
Current gain Ic=βIBIc=βIB
Selection rule for rotational energy transitions Δl=±1Δl=±1
Selection rule for vibrational energy transitions Δn=±1Δn=±1
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