I was just testing this and agree with @jmisiewicz. The below runs just fine and contains all the likely tripping points – iodine, ct, higher-order SAPT. Do you really need the components breakdown from SAPT2+(3)? SAPT0 generally gives good qualitative components, while for overall interaction energy, CCSD(T) will be more accurate than SAPT2+(3).
memory 30 Gb
molecule C6F4I2_a_Dimer {
0 1
H 0.0 0.0 0.0
I 1.5 0.0 0.0
--
H 1.5 3.0 0.0
I 0.0 3.0 0.0
units angstrom
}
set globals {
basis def2-tzvp
df_basis_scf def2-tzvp-jkfit
df_basis_sapt def2-tzvp-ri
df_basis_elst def2-tzvp-jkfit
scf_type df
}
energy('sapt2+(3)-ct')