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<<TableOfContents(4)>>

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).