Differences between revisions 6 and 24 (spanning 18 versions)

Contents

RESP module for response properties based on HF and DFT
Quick guides by examples
Some caveats before using this module
1. 1. dft
  2. scf

RESP module for response properties based on HF and DFT

Keywords for general information

IPRT

Print level, >1 gives more information, >2 give more information about integral evaluations.

NPRT

CHCK

Check the interface with several external packages.

CTHRD

Keyworks for processing excited-state information

METHOD

=1, ground state gradients; =2, excited-state calculations which will load TD-DFT output.

NFILES

Linked with istore value in TD-DFT input for loading output.

Keyword for geometric derivatives

GEOM: NORDER

GEOM enables geometric derivatives, NORDER=1, gradient and fo-NACMEs; =2, hessian (not implemented yet.)

Keywords for linear response calculations

LINE

Enable linear response

REDUCED

Solve the response equation in its reduced form [(A-B)(A+B)-w2](X+Y)=Rvo+Rov (not preferred).

POLA: AOPER, BOPER, BFREQ

Polarizabiity: <<A;B>>(wB), where the operators A and B can be dipole (DIP), quadruple (QUA), SOC (HSO), EFG.

Keywords for quadratic response calculations

QUAD

Enable quadratic response function (QRF) calculations

HYPE: AOPER, BOPER, BFREQ, COPER, CFREQ

Hyperpolarizability: <<A;B,C>>(wB,wC)

SINGLE:STATES

Single residue of QRF, STATES can be used to specify the number of states followed by a detailed specification via the triple (ifile,isym,istate).

DOUBLE: PAIRS

Double residue of QRF, PAIRS can be used to specify the number of pairs followed by a detailed specification via two triples (ifile,isym,istate,jfile,isym,jstate).

FNAC

First-order nonadiabatic couplings

NORESP

Neglect the response part of transition density matrix in DOUBLE and FNAC calculations (recommended)

Keywords for finite difference calculations

FDIF

Enable finite difference calculations

STEP

followed by a real number for the step size, default 0.001 [unit].

BOHR

The default unit is angstrom, to use bohr. This keyword must be specified.

IGNORE

Ignore the recomputation of excitation energies for check consistency.

Quick guides by examples

The following examples give the minimal inputs for starting response calculations:

Ground-state geometric derivatives Response properties based on response functions Excited-state properties based on analytic derivatives Examples: first-order nonadiabatic couplings Examples: pp-TDA based properties

Some caveats before using this module

dft

1. Thresholds in dft_prescreen.F90 have set very tight.

2. Keyword ixcfun in SCF allows to use original XC library (default) or XCFun lib (=1) by Ulf Ekström [http://www.admol.org/xcfun] in dft and tddft.

scf

1. Sgnfix: fix adjacent sign

2. iaufbau=3: fix ordering and sign with respect to the initial MOs.

3. Convergence

-  ⇤ ← Revision 6 as of 2014-09-25 14:32:34 → 
  Size: 3101
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  Comment:
+   ← Revision 24 as of 2014-09-27 02:45:10 → ⇥
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  Comment:
-Deletions are marked like this.
+Additions are marked like this.
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-= resp =
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-{{{
Response properties based on DFT/HF theory. 
}}}
+= RESP module for response properties based on HF and DFT =
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+Line 15:
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-== Keyworks for processing excited-state information ===
+== Keyworks for processing excited-state information ==
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-=== GEOM: NORDER  ===
+=== GEOM: NORDER ===
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-===  LINE ===
Enable linear response
+=== LINE ===
Enable linear response
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+Line 35:
+Solve the response equation in its reduced form [(A-B)(A+B)-w2](X+Y)=Rvo+Rov (not preferred).
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+Polarizabiity: '''<<A;B>>(wB)''', where the operators A and B can be dipole (DIP), quadruple (QUA), SOC (HSO), EFG.
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+Line 40:
+== Keywords for quadratic response calculations ==
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+Line 42:
+Enable quadratic response function (QRF) calculations
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+Line 45:
+Hyperpolarizability: '''<<A;B,C>>(wB,wC)'''

=== SINGLE:STATES ===
Single residue of QRF, STATES can be used to specify the number of states followed by a detailed specification via the triple (ifile,isym,istate).

=== DOUBLE: PAIRS ===
Double residue of QRF, PAIRS can be used to specify the number of pairs followed by a detailed specification via two triples (ifile,isym,istate,jfile,isym,jstate).
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+Line 54:
-=== SINGLE:STATES ===

=== DOUBLE: PAIRS ===
+First-order nonadiabatic couplings
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+Line 57:
+Neglect the response part of transition density matrix in DOUBLE and FNAC calculations (recommended)
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+Line 59:
-== FDIF ==
+== Keywords for finite difference calculations ==
=== FDIF ===
Enable finite difference calculations
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+Line 64:
+followed by a real number for the step size, default 0.001 [unit].
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+Line 67:
+The default unit is angstrom, to use bohr. This keyword must be specified.
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+=== IGNORE ===
Ignore the recomputation of excitation energies for check consistency.
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-== IGNORE ==

== Quick guides by examples ==
+= Quick guides by examples =
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-=== Example: first-order NAC ===
+[[Ground-state geometric derivatives]]
[[Response properties based on response functions]]
[[Excited-state properties based on analytic derivatives]]
[[Examples: first-order nonadiabatic couplings]]
[[Examples: pp-TDA based properties]]
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-{{{
+= Some caveats before using this module =
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-$COMPASS
Title
 nh3
Basis
 sto-3g
Geometry
 C                  0.00000000   -1.20809142   -1.14173975
 C                  0.00000000   -1.20797607    0.25342015
 C                  0.00000000    0.00000000    0.95085852
 C                 -0.00000000    1.20797607    0.25342015
 C                 -0.00000000    1.20809142   -1.14173975
 C                  0.00000000    0.00000000   -1.83922155
 H                  0.00000000   -2.16045397   -1.69142002
 H                  0.00000000   -2.16044427    0.80300713
 H                 -0.00000000    2.16044427    0.80300713
 H                 -0.00000000    2.16045397   -1.69142002
 H                  0.00000000    0.00000000   -2.93882555
 F                  0.00000000    0.00000000    2.30085848
End geometry
skeleton
group
c(1)
nosym
$END
+=== dft ===
1. Thresholds in dft_prescreen.F90 have set very tight.
-Line 105:
+Line 86:
-$xuanyuan
direct
schwarz
$end
+. Keyword '''ixcfun''' in SCF allows to use original XC library (default) or XCFun lib (=1) by Ulf Ekström [http://www.admol.org/xcfun] in dft and tddft.
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+Line 88:
-$scf
RHF
charge
0
spin
1
THRESHCONV
1.d-10 1.d-8
OPTSCR
1
iaufbau
0
$end
+=== scf ===
1. Sgnfix: fix adjacent sign
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+Line 91:
-$tddft
imethod
1
isf
0
iexit
2
itda
1
idiag
1
istore
1
crit_e
1.d-10
crit_vec
1.d-8
lefteig
AOKXC
DirectGrid
$end
+. iaufbau=3: fix ordering and sign with respect to the initial MOs.
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+Line 93:
-$resp
iprt
1
QUAD
FNAC
single
states
1
1 1 2
double
pairs
1
1 1 1 1 1 2
norder
1
method
2
nfiles
1
FDIF
step
0.001
ignore
1
noresp
$end

}}}

To use finite-difference, a script '''fdiff.py''' should be used as
{{{
./fbdiff.py run.sh input.inp > log
}}}
After the calculation is done, an output file '''input.out''' will present in the current directory. The '''log''' file saves the information during the calculations.

Note: If '''FDIF''' is omitted, the analytic calculation will be carried out by simply using the '''run.sh''' script.
+. Convergence

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