input file basic form

usually to calculate HOMO and LUMO, we first optimize the structure and then we calculate the energy（单点能），which includes the kinetic and potential energy of the electrons.

To calulate the optimaze structure

%nprocshared=2
%mem=300MW
%chk=C:\Users\Administrator.SKY-20190610LKN\Desktop\11.chk
# opt freq b3lyp/3-21g* em=gd3bj scrf=(smd,solvent=THF)

optimization of benzene, we need to change the method and basic set.

# opt freq b3lyp/6-31g(d) em=gd3bj scrf=(smd,solvent=THF)

To calulate 单点能

%nprocshared=2
%mem=300MW
%chk=C:\Users\Administrator.SKY-20190610LKN\Desktop\Cu.chk
# b3lyp/3-21g em=gd3bj scrf=(smd,solvent=THF)

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to calculate before uvvis

%nprocshared=2
%mem=100MW
%chk=C:\Users\Administrator.SKY-20190610LKN\Desktop\C24uvvis.chk
# td b3lyp/6-31g* em=gd3bj scrf=(smd,solvent=THF)