7.8 Coupled-Cluster Excited-State and Open-Shell Methods

7.8.14 Examples

Example 7.35  EOM-EE-OD and EOM-EE-CCSD calculations of the singlet excited states of formaldehyde.

$molecule
   0 1
   O
   C  1  R1
   H  2  R2  1  A
   H  2  R2  1  A  3  180.

   R1  =  1.4
   R2  =  1.0
   A   =  120.
$end

$rem
   METHOD      eom-od
   BASIS       6-31+g
   EE_STATES   [2,2,2,2]
$end

@@@

$molecule
   read
$end

$rem
   METHOD        eom-ccsd
   BASIS         6-31+g
   EE_SINGLETS   [2,2,2,2]
   EE_TRIPLETS   [2,2,2,2]
$end

Example 7.36  EOM-EE-CCSD calculations of the singlet excited states of water using Cholesky decomposition.

$molecule
0 1
O           0.000000    0.000000   -0.069336
H          -0.759081    0.000000   -0.665332
H           0.759081    0.000000   -0.665332
$end

$rem
   METHOD          eom-ccsd
   BASIS           aug-cc-pVDZ
   PURECART        1112
   N_FROZEN_CORE   fc
   CC_T_CONV       4
   CC_E_CONV       6
   CHOLESKY_TOL    2    using CD/1e-2 threshold
   EE_SINGLETS     [2,2,0,0]
$end

Example 7.37  EOM-SF-CCSD calculations for methylene from high-spin 3B2 reference.

$molecule
   0 3
   C
   H  1 rCH
   H  1 rCH 2 aHCH

   rCH   = 1.1167
   aHCH  = 102.07
$end

$rem
   METHOD      eom-ccsd
   BASIS       6-31G*
   SCF_GUESS   core
   SF_STATES   [2,0,0,2]   Two singlet A1 states and singlet and triplet B2 states
$end

Example 7.38  EOM-SF-MP2 calculations for SiH2 from high-spin 3B2 reference. Both energies and properties are computed.

$molecule
   0 3
   Si
   H  1 1.5145
   H  1 1.5145 2 92.68
$end

$rem
   BASIS            = cc-pVDZ
   UNRESTRICTED     = true
   SCF_CONVERGENCE  = 8
   METHOD           = eom-mp2
   SF_STATES        = [1,1,0,0]
   CC_EOM_PROP_TE   = true   ! Compute <S^2> of excited states
$end

Example 7.39  EOM-IP-CCSD calculations for NO3 using closed-shell anion reference.

$molecule
   -1 1
   N
   O  1  r1
   O  1  r2   2 A2
   O  1  r2   2 A2    3 180.0

   r1    = 1.237
   r2    = 1.237
   A2    = 120.00
$end

$rem
   METHOD       eom-ccsd
   BASIS        6-31G*
   IP_STATES    [1,1,2,1]    ground and excited  states of the radical
$end

Example 7.40  EOM-IP-CCSD calculation using FNO with OCCT=99%.

$molecule
   0 1
   O
   H  1  1.0
   H  1  1.0  2  100.
$end

$rem
   METHOD          eom-ccsd
   BASIS           6-311+G(2df,2pd)
   IP_STATES       [1,0,1,1]
   CC_FNO_THRESH   9900        99% of the total natural population recovered
$end

Example 7.41  EOM-IP-MP2 calculation of the three low lying ionized states of the phenolate anion.

$molecule
   0 1
   C   -0.189057  -1.215927  -0.000922
   H   -0.709319  -2.157526  -0.001587
   C    1.194584  -1.155381  -0.000067
   H    1.762373  -2.070036  -0.000230
   C    1.848872   0.069673   0.000936
   H    2.923593   0.111621   0.001593
   C    1.103041   1.238842   0.001235
   H    1.595604   2.196052   0.002078
   C   -0.283047   1.185547   0.000344
   H   -0.862269   2.095160   0.000376
   C   -0.929565  -0.042566  -0.000765
   O   -2.287040  -0.159171  -0.001759
   H   -2.663814   0.725029   0.001075
$end

$rem
   THRESH      16
   CC_MEMORY   30000
   BASIS       6-31+g(d)
   METHOD      eom-mp2
   IP_STATES   [3]
$end

Example 7.42  EOM-EE-MP2T calculation of the H2 excitation energies.

$molecule
   0 1
   H   0.0000   0.0000   0.0000
   H   0.0000   0.0000   0.7414
$end

$rem
   THRESH     16
   BASIS      cc-pvdz
   METHOD     eom-mp2t
   EE_STATES  [3,0,0,0,0,0,0,0]
$end

Example 7.43  EOM-EA-CCSD calculation of CN using user-specified guess.

$molecule
   +1 1
   C
   N  1  1.1718
$end

$rem
   METHOD          = eom-ccsd
   BASIS          = 6-311+g*
   EA_STATES      = [1,1,1,1]
   CC_EOM_PROP    = true
   EOM_USER_GUESS = true   ! attach to HOMO, HOMO+1, and HOMO+3
$end

$eom_user_guess
   1  2  4
$end

Example 7.44  DSF-CIDT calculation of methylene starting with quintet reference.

$molecule
   0 5
   C
   H 1 CH
   H 1 CH 2 HCH

   CH  = 1.07
   HCH = 111.0
$end

$rem
   METHOD               cisdt
   BASIS                6-31G
   DSF_STATES           [0,2,2,0]
   EOM_NGUESS_SINGLES   0
   EOM_NGUESS_DOUBLES   2
$end

Example 7.45  EOM-EA-CCSD job for cyano radical. We first do Hartree-Fock calculation for the cation in the basis set with one extremely diffuse orbital (EOM_FAKE_IPEA) and use these orbitals in the second job. We need make sure that the diffuse orbital is occupied using the OCCUPIED keyword. No SCF iterations are performed as the diffuse electron and the molecular core are uncoupled. The attached states show up as “excited” states in which electron is promoted from the diffuse orbital to the molecular ones.

$molecule
   +1 1
   C
   N 1 bond

   bond   1.1718
$end

$rem
   METHOD            hf
   BASIS             6-311+G*
   PURECART          111
   SCF_CONVERGENCE   8
   EOM_FAKE_IPEA     true
$end

@@@

$molecule
   0 2
   C
   N 1 bond

   bond   1.1718
$end

$rem
   BASIS            6-311+G*
   PURECART         111
   SCF_GUESS        read
   MAX_SCF_CYCLES   0
   METHOD           eom-ccsd
   CC_DOV_THRESH    2501   use thresh for CC iters with convergence problems
   EA_STATES        [2,0,0,0]
   EOM_FAKE_IPEA    true
$end

$occupied
   1 2 3 4 5 6 14
   1 2 3 4 5 6
$end

Example 7.46  DIP-EOM-CCSD calculation of methylene with charged cage stabilization.

$molecule
   -2 1
   C   0.000000     0.000000     0.106788
   H  -0.989216     0.000000    -0.320363
   H   0.989216     0.000000    -0.320363
$end

$rem
   BASIS                    = 6-311g(d,p)
   SCF_ALGORITHM            = diis_gdm
   SYMMETRY                 = false
   METHOD                   = eom-ccsd
   CC_SYMMETRY              = false
   DIP_SINGLETS             = [1]  ! Compute one EOM-DIP singlet state
   DIP_TRIPLETS             = [1]  ! Compute one EOM-DIP triplet state
   EOM_DAVIDSON_CONVERGENCE = 5
   CC_EOM_PROP              = true ! Compute excited state properties
   ADD_CHARGED_CAGE         = 2    ! Install a charged sphere around the molecule
   CAGE_RADIUS              = 225  ! Radius = 2.25 A
   CAGE_CHARGE              = 500  ! Charge = +5 a.u.
   CAGE_POINTS              = 100  ! Place 100 point charges
   CC_MEMORY                = 256  ! Use 256Mb of memory, increase for larger jobs
$end

Example 7.47  EOM-EE-CCSD calculation of excited states in NO- using scaled nuclear charge stabilization method.

$molecule
   -1 1
    N  -1.08735    0.0000    0.0000
    O   1.08735    0.0000    0.0000
$end

$rem
   INPUT_BOHR           = true
   BASIS                = 6-31g
   SYMMETRY             = false
   CC_SYMMETRY          = false
   METHOD               = eom-ccsd
   EE_SINGLETS          = [2]  ! Compute two EOM-EE singlet excited states
   EE_TRIPLETS          = [2]  ! Compute two EOM-EE triplet excited states
   CC_REF_PROP          = true ! Compute ground state properties
   CC_EOM_PROP          = true ! Compute excited state properties
   CC_MEMORY            = 256  ! Use 256Mb of memory, increase for larger jobs
   SCALE_NUCLEAR_CHARGE = 180  ! Adds +1.80e charge to the molecule
$end

Example 7.48  EOM-EE-CCSD calculation for formamide with user-specified guess requesting the EE transition from the occupied orbital number 12 (2 A") to the virtual orbital number 1 (11 A’).

$molecule
0 1
N         1.0706214490   -0.1462996030    0.0000000000
C        -0.1838756809    0.3832287690    0.0000000000
O        -1.2178351723   -0.2734201303    0.0000000000
H         1.8945772136    0.4351761203    0.0000000000
H         1.1761147729   -1.1515954431    0.0000000000
H        -0.1740335498    1.4879608698    0.0000000000
$end

$rem
   METHOD                     EOM-CCSD
   BASIS                      6-31+G(d,p)
   CC_MEMORY                  3000   ccman2 memory
   MEM_STATIC                 250
   CC_T_CONV                  4      T-amplitudes convergence threshold
   CC_E_CONV                  6      Energy convergence threshold
   EE_STATES                  [0,1]  Calculate 1 A" states
   EOM_DAVIDSON_CONVERGENCE   5      Convergence threshold for the Davidson procedure
   !EOM_USER_GUESS             true   Use user guess from $eom_user_guess section
$end

$eom_user_guess
   12
   1
$end

Example 7.49  CAP-augmented EOM-EA-CCSD calculation for N-2. aug-cc-pVTZ basis augmented by the 3s3p3d diffuse functions placed in the COM. Two EA states are computed for CAP strength η=0.002.

$molecule
   0 1
   N   0.0  0.0 -0.54875676501
   N   0.0  0.0  0.54875676501
   Gh  0.0  0.0  0.0
$end

$rem
   COMPLEX_CCMAN   1             engage complex_ccman
   METHOD          EOM-CCSD
   BASIS           gen           use general basis
   EA_STATES       [0,0,2,0,0,0,0,0]  compute electron attachment energies
   CC_MEMORY       2000          ccman2 memory
   MEM_TOTAL       4000
   CC_EOM_PROP     true          compute excited state properties
$end

$complex_ccman
   CS_HF           1     Use complex HF
   CAP_ETA         200   Set strength of CAP potential 0.002
   CAP_X           2760  Set length of the box along x dimension
   CAP_Y           2760  Set length of the box along y dimension
   CAP_Z           4880  Set length of the box along z dimension
   CAP_TYPE        1     Use cuboid CAP
$end

$basis
N    0
aug-cc-pvtz
****
Gh   0
S    1    1.000000
   2.88000000E-02    1.00000000E+00
S    1    1.000000
   1.44000000E-02    1.00000000E+00
S    1    1.000000
   0.72000000E-02    1.00000000E+00
P    1    1.000000
   2.45000000E-02    1.00000000E+00
P    1    1.000000
   1.22000000E-02    1.00000000E+00
P    1    1.000000
   0.61000000E-02    1.00000000E+00
D    1    1.000000
   0.755000000E-01   1.00000000E+00
D    1    1.000000
   0.377500000E-01   1.00000000E+00
D    1    1.000000
   0.188750000E-01   1.00000000E+00
****
$end

Example 7.50  CAP-EOM-EE calculation of water, with wave-function analysis of state and transition properties.

$molecule
   0 1
   O   0.00000000     0.00000000     0.13594219
   H   0.00000000    -1.44761450    -1.07875060
   H   0.00000000     1.44761450    -1.07875060
$end

$rem
   METHOD                     eom-ccsd
   BASIS                      6-31G**
   CC_MEMORY                  2000
   MEM_TOTAL                  2500
   SCF_CONVERGENCE            12
   CC_CONVERGENCE             11
   EOM_DAVIDSON_CONVERGENCE   11
   CC_EOM_PROP                TRUE
   CC_FULLRESPONSE            FALSE
   CC_TRANS_PROP              TRUE
   COMPLEX_CCMAN              1
   EE_STATES                  [1,0,2,0]
   INPUT_BOHR                 TRUE
   ! WFA KEYWORDS
   STATE_ANALYSIS             true
   MOLDEN_FORMAT              true
   NTO_PAIRS                  4
   POP_MULLIKEN               true
$end

$complex_ccman
CS_HF           1
CAP_TYPE        1
CAP_ETA         10000
CAP_X           2000
CAP_Y           2500
CAP_Z           2500
$end

Example 7.51  CAP-EOM-EA-CCSD calculation of π* shape resonance in CO- using Voronoi’s CAP.

$molecule
0  1
C    0.0   0.0    0.5640000000
O    0.0   0.0   -0.5640000000
Gh   0.0   0.0    0.0
$end

$rem
   METHOD            eom-ccsd
   BASIS            gen
   EA_STATES        [0,0,5,0]
   COMPLEX_CCMAN    1
   XC_GRID          000099000590
   N_FROZEN_CORE    FC
$end

$complex_ccman
   CS_HF      1
   CAP_TYPE   2
   CAP_ETA    640
   CAP_X      2765
$end

$basis
C     0
aug-cc-pvtz
****
O     0
aug-cc-pvtz
****
Gh      0
S   1   1.00
      0.0588900              1.0000000
S   1   1.00
      0.0294450              1.0000000
S   1   1.00
      0.0147225              1.0000000
P   1   1.00
      0.0238575              1.0000000
P   1   1.00
      0.01192875             1.0000000
P   1   1.00
      0.005964375            1.0000000
D   1   1.00
      0.0785000              1.0000000
D   1   1.00
      0.0392500              1.0000000
D   1   1.00
      0.0196250              1.0000000
****
$end

Example 7.52  Projected CAP-EOM-EE-CCSD calculation of H2, with CAP added at the CCSD step.

$molecule
0 1
H 0.0000 0.0000 0.0000
H 0.0000 0.0000 0.7414
$end

$rem
jobtype sp
thresh 16
basis cc-pvdz
method eom-ccsd
ee_states [5,0,0,0,0,0,0,0]
complex_ccman 1
$end

$complex_ccman
PROJ_CAP 1
CS_HF 0
CAP_ETA 1000
CAP_X 2000
CAP_Y 2000
CAP_Z 2000
$end

Example 7.53  Projected CAP-EOM-EA-MP2T η-trajectory generation for the first three states of H2-, with CAP applied at the EOM step.

$molecule
0 1
H 0.0000 0.0000 0.0000
H 0.0000 0.0000 0.7414
$end

$rem
   THRESH         16
   BASIS          cc-pvdz
   METHOD         eom-mp2t
   EA_STATES      [3,0,0,0,0,0,0,0]
   COMPLEX_CCMAN  1
$end

$complex_ccman
   PROJ_CAP  2
   ETA_STEP  100      ETA step
   CAP_ETA   1000      Initial ETA value
   NSTEPS    20         Number of steps along the trajectory
   CAP_X     2000
   CAP_Y     2000
   CAP_Z     2000
$end

Example 7.54  Formaldehyde, calculating EOM-IP-CCSD-S(D) and EOM-IP-MP2-S(D) energies of 4 valence ionized states.

$molecule
   0 1
   C
   H  1  1.096135
   H  1  1.096135  2  116.191164
   O  1  1.207459  2  121.904418  3  -180.000000 0
$end

$rem
   METHOD       eom-ccsd-s(d)
   BASIS        6-31G*
   IP_STATES    [1,1,1,1]
$end

@@@

$molecule
   read
$end

$rem
   METHOD       eom-mp2-s(d)
   BASIS        6-31G*
   IP_STATES    [1,1,1,1]
$end

Example 7.55  Formaldehyde, calculating EOM-EE-CCSD states with C-PCM method.

$molecule
   0 1
   O
   C,1,R1
   H,2,R2,1,A
   H,2,R2,1,A,3,180.

   R1 = 1.4
   R2 = 1.0
   A  = 120.
$end

$rem
   METHOD           eom-ccsd
   BASIS            cc-pvdz
   EE_STATES        [4]
   SOLVENT_METHOD   pcm
$end

$pcm
   theory          cpcm
$end

$solvent
   dielectric      4.34
   dielectric_infi 1.829
$end

Example 7.56  NO-2, calculating EOM-IP-CCSD states with C-PCM method.

$molecule
   -1 1
   N1
   O2 N1 RNO
   O3 N1 RNO O2 AONO

   RNO  = 1.305
   AONO = 106.7
$end

$rem
   METHOD           eom-ccsd
   BASIS            cc-pvdz
   IP_STATES        [2]
   SOLVENT_METHOD   pcm
$end

$pcm
   theory          cpcm
$end

$solvent
   dielectric      4.34
   dielectric_infi 1.829
$end