nrcc

The non-relativistic restricted CCD/CCSD/EOM-IP-CCSD/EOM-EA-CCSD/EOM-EE-CCSD program, translated from pyscf of Qiming Sun.

Keywords

The 3 EOM-CCSD method can be written in one section, this will reduce time calculating intermediates. With EOM Ketwords, the reference CCSD amplitudes will be loaded from ".ccsd" file if it exists, otherwise CCSD calculation will be automatically performed.

method

CCSD

Default option. Amplitudes are saved in ".ccsd" file.

CCD

Amplitudes are saved in ".ccd" file.

EOMIPCCSD

EOM-IP-CCSD Calculation.

EOMEACCSD

EOM-EA-CCSD Calculation.

EOMEECCSDS

EOM-EE-CCSD Calculation (Singlet).

EOMEECCSDT

EOM-EE-CCSD Calculation (Triplet (ms=0)).

EOMEECCSDF

EOM-EE-CCSD Calculation (Spin flip tp triplet (ms=1)).

CC control

NODIIS

Turn off DIIS of CC. This will often lead to not converge.

CONV

The Delta E for CC converge. Default 1e-7.

MAXCYC

Max iterations for CC. Default 1000.

MAXDIIS

DIIS space size (+1), default 8 (size 7).

EOM control

The partial diagonalization uses iVI.

NROOT

Number of wanted exterior roots in EOM-IP/EA/EE-CCSD. 0 or >0.1*(matrix dimention) for full diagonalization; <0: begin advanced mode (batch/interior roots)

IPNROOT

EANROOT

EESNROOT

EETNROOT

EEFNROOT

EOMCONV

The Delta E for iVI-EOM-IP/EA/EE-CCSD.

EOMIPCONV

EOMEACONV

EOMEESCONV

EOMEETCONV

EOMEEFCONV

NOAMP

Don't perform amplitude analysis.

NOAMPIP

NOAMPEA

NOAMPEES

NOAMPEET

NOAMPEEF

EOM advaced mode

Extra input files ($BDFTASK.eomip.inpx / $BDFTASK.eomea.inpx / $BDFTASK.eomee.inpx) need to be placed under $BDF_WORKDIR (usually same as the place input file located). Users should make the input correct! Or unexpected error may occur!

First parameter is N, specific N sections in the extra input file. Each section starts with either "eivi" or "iivi", ends with "end". For "eivi", M should be followed as the number of exterior roots. For "iivi", el er should be followed as the energy window. the additional keywords are

CONV

The Delta E for iVI/

NOAMP

Don't perform amplitude analysis.

MAXCYC

Max iteration numbers.

MLD

Estimate the number for interior roots. Default 150. Change it when interior iVI crash (usually should make it larger unless the crash is because of memory limit).