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EOM-CCSD and EOM-CCSD(t) energies same

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Author Post
Member
Registered: Oct 2017
Posts: 3
Dear all,

I had run an EOM-IP-CCSD calculation to compute the ionization energies of various ionized states of my system. In order to improve the results I also ran an EOM-CCSD with triplet correction job. However I do not see any changes in the ionization energies from the EOM-CCSD values. They are exactly same. Also the triplet correction to the EOM-CCSD wave function is absent in the output of EOM-CCSD(t). Could someone please correct me where I am going wrong ?

Any suggestion/help will be highly appreciated. Following are the $rem parts of the inputs for the EOM-CCSD and EOM-CCSD(t)
jobs respectively-


Quote
EOM-CCSD

$rem
basis general
ecp general
max_scf_cycles 200
cc_symmetry false
sym_ignore true
ccman2 true
method eom-ccsd
purecart 111
ip_states [12] !Target EOM-IP states
cc_trans_prop true
cc_do_dyson true
mem_static 2000
cc_memory 10000
print_general_basis true
ianlty true
make_cube_files true
$end


EOM-CCSD(t)

$rem
basis general
ecp general
max_scf_cycles 200
cc_symmetry false
sym_ignore true
ccman2 true
correlation ccsd
eom_corr sd(ft)
purecart 111
ip_states [12] !Target EOM-IP states
cc_trans_prop true
cc_do_dyson true
mem_static 2000
cc_memory 10000
print_general_basis true
ianlty true
make_cube_files true
$end
Administrator
Registered: Oct 2017
Posts: 17
Which version of Q-Chem is it? The keywords "correlation" and "eom_corr" in ccman2 jobs are deprecated. Does "method = eom-ccsd(ft)" give the same problem?

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