I have received your input file. The keyword you used is strange: "RHF/6-31G(d,p) Polar=(DCSHG,Cubic)". Note that Gaussian supports third-order analytic derivative at HF level, therefore "cubic" should not be used. This keyword is only meaningful for methods only supporting second-order analytic derivative, such as MP2.

Second, DCSHG calculation reads frequencies from end of the input file. I don't know which kind of hyperpolarizability is the one you really need, beta(0;0,0), Beta(-w;w,0) or Beta(-2w;w,w)? If you need the latter two types, the frequency specified at the end of input file should not be zero, however in your current file the value is 0.0.

Below is an example input file

#p PBE1PBE/aug-cc-pVDZ Polar=DCSHG Title Card Required 0 1 C 0.00000000 0.00000000 -1.45735930 C 0.00000000 -1.20820358 -0.75960440 C 0.00000000 -1.20821204 0.63510756 C 0.00000000 0.00000000 1.33270547 C -0.00000000 1.20821204 0.63510756 C -0.00000000 1.20820358 -0.75960440 H 0.00000000 0.00000000 -2.55696958 H 0.00000000 -2.16044354 1.18515445 H 0.00000000 0.00000000 2.43238549 H -0.00000000 2.16044354 1.18515445 0.05

The beta(-2w;w,w) can be normally outputted by Multiwfn, the output information is attached:
out.txt

Dear Wesley,

Currently Multiwfn doesn't support parsing the output file of polar=gamma.
Please send me the input and output file of polar=(DCSHG,Cubic) task via my E-mail (see first page of Multiwfn manual), I will check the reason why it cannot be properly parsed.

Best regards,

Tian

I performed a calculations to obtained the results of gamma using Gaussian and keyword polar=gamma or polar=(DCSHG,Cubic). However, when I try obtain values using multiwfn, the program closes. Other parameter such as alfa and beta work correctly. Can someone help me?