Multiwfn forum / Multiwfn and wavefunction analysis

Wave function analysis at DLPNO-CCSD(T)

dummy@example.com (saeed_E) — Tue, 23 Jun 2026 16:06:59 +0000

NOO means natural orbital occupancies.
You so kindly mentioned:
Also you can use the MDCI code in ORCA to obtain CCSD unrelaxed density (or density corresponding to CCD with orbital optimization) to yield NOO, the efficiency is much higher than the AUTOCI-CCSD while the accuracy is not much poorer than the CCSD relaxed density. Alternatively, using Gaussian to yield CCSD relaxed density, it is not quite expensive for your system.

Could you please let me know what should be the ORCA input file for my system exactly? In addition, the orca.jason.conf should be created. Please also let me know what should be its contents to be used in Multiwfn (1000--->98).

Sincerely,
Saeed

ESP Scale Change

dummy@example.com (alexlester1996) — Sun, 21 Jun 2026 19:32:15 +0000

Dr Tian,
Thank you for this helpful comment.
Best wishes,
Alex

IFCT / Electron excitation analysis / ORCA /json / problem

dummy@example.com (sobereva) — Sat, 20 Jun 2026 11:19:40 +0000

Multiwfn can load configurational coefficients from either ORCA output file or json file. As stated in the prompt, because current TDDFT calculation is based on an open-shell reference state (doublet ground state), Multiwfn cannot load coefficients from the json file despite you provided it (because current version of ORCA has a bug in outputting json file) but automatically load coefficients from ORCA output file. In this case, the analysis result may be inaccurate with "TDA false"

It is expected that next release of ORCA revision will solve this bug, at that time, I will update Multiwfn, then this difficulty will be perfectly solved.

Segmentation fault using LIBRETA for RESP calculation

dummy@example.com (sobereva) — Thu, 18 Jun 2026 00:03:20 +0000

Dear Marcos,

I can normally run the calculation using your files on my RockyLinux 10 computer with Multiwfn 2026.6.2. Using 96 cores, the calculation is finished in about half a minute. All outputted information is given below:

 Multiwfn -- A Multifunctional Wavefunction Analyzer
 Version 2026.6.2 (release date is the same as version name)
 Developer: Tian Lu (Beijing Kein Research Center for Natural Sciences)
 Multiwfn official website: http://sobereva.com/multiwfn
 Multiwfn English forum: http://sobereva.com/wfnbbs
 Multiwfn Chinese forum: http://bbs.keinsci.com/wfn
 ( Number of parallel threads:  96  Current date: 2026-06-17  Time: 23:59:38 )

 Both following papers ***MUST BE CITED IN MAIN TEXT*** if Multiwfn is used:

  Tian Lu, Feiwu Chen, J. Comput. Chem., 33, 580 (2012) DOI: 10.1002/jcc.22885
  Tian Lu, J. Chem. Phys., 161, 082503 (2024) DOI: 10.1063/5.0216272

 See "How to cite Multiwfn.pdf" in Multiwfn binary package for more information

 Now input file path, for example, E:\Strawberry_Panic\Chikaru_Minamoto.mwfn
 (.mwfn/wfn/wfx/fch/molden/pdb/xyz/mol2/cif/cub... see Section 2.5 of manual)
 Hint: Pressing ENTER button directly can select a file in a GUI window. To reload the past file, inputting "o". Input such as ?miku.fch can open the miku.fch in the same folder as the past file
esp_0.molden.input
 Please wait...
 Loading various information of the wavefunction
 This file is recognized to be generated by ORCA because there is "orca" word in title line. Special treatments are applied...
 Loading basis set definition...
 All D basis functions are spherical harmonic type
 Loading orbitals...
 The actual number of orbitals read:       470
 Converting basis function information to GTF information...
 Back converting basis function information from Cartesian to spherical type...
 Generating density matrix...
 Generating overlap matrix...

 Total/Alpha/Beta electrons:    260.0000    130.0000    130.0000
 Net charge:    -4.00000      Expected multiplicity:    1
 Atoms:     43,  Basis functions:    470,  GTFs:    988
 This is a restricted single-determinant wavefunction
 Orbitals from 1 to   130 are occupied

 Loaded esp_0.molden.input successfully!

 Formula: H12 C10 N5 O13 P3      Total atoms:      43
 Molecule weight:       503.14971 Da
 Point group: C1

 "q": Exit program gracefully          "r": Load a new file
                    ************ Main function menu ************
 0 Show molecular structure and view orbitals
 1 Output all properties at a point       2 Topology analysis
 3 Output and plot specific property in a line
 4 Output and plot specific property in a plane
 5 Output and plot specific property within a spatial region (calc. grid data)
 6 Check & modify wavefunction
 7 Population analysis and calculation of atomic charges
 8 Orbital composition analysis           9 Bond order analysis
 10 Plot total DOS, PDOS, OPDOS, local DOS, COHP and photoelectron spectrum
 11 Plot IR/Raman/UV-Vis/ECD/VCD/ROA/NMR spectrum
 12 Quantitative analysis of molecular surface
 13 Process grid data (No grid data is presented currently)
 14 Adaptive natural density partitioning (AdNDP) analysis
 15 Fuzzy atomic space analysis
 16 Charge decomposition analysis (CDA) and plot orbital interaction diagram
 17 Basin analysis                       18 Electron excitation analysis
 19 Orbital localization analysis        20 Visual study of weak interaction
 21 Energy decomposition analysis        22 Conceptual DFT (CDFT) analysis
 23 ETS-NOCV analysis                    24 (Hyper)polarizability analysis
 25 Electron delocalization and aromaticity analyses
 26 Structure and geometry related analyses
 100 Other functions (Part 1)            200 Other functions (Part 2)
 300 Other functions (Part 3)
7
 NOTE: There is a review comprehensively introducing various atomic charges:
 Tian Lu, Qinxue Chen, Partial Charges, In Exploring Chemical Concepts Through T
 heory and Computation. WILEY-VCH GmbH: Weinheim (2024); pp. 161-187. DOI: 10.10
 02/9783527843435.ch6

      ============== Population analysis and atomic charges ==============
 -2 Calculate interaction energy between fragments based on atomic charges
 -1 Define fragment
 0 Return
 1 Hirshfeld atomic charge
 2 Voronoi deformation density (VDD) atom population
 5 Mulliken atom & basis function population analysis
 6 Lowdin atom & basis function population analysis
 7 Modified Mulliken atom population defined by Ros & Schuit (SCPA)
 8 Modified Mulliken atom population defined by Stout & Politzer
 9 Modified Mulliken atom population defined by Bickelhaupt
 10 Becke atomic charge with atomic dipole moment correction
 11 Atomic dipole corrected Hirshfeld atomic charge (ADCH) (recommended)
 12 CHELPG ESP fitting atomic charge
 13 Merz-Kollmann (MK) ESP fitting atomic charge
 14 AIM atomic charge
 15 Hirshfeld-I atomic charge
 16 CM5 atomic charge    -16 Generate 1.2*CM5 atomic charge
 17 Electronegativity Equalization Method (EEM) atomic charge
 18 Restrained ElectroStatic Potential (RESP) atomic charge
 19 Gasteiger (PEOE) charge
 20 Minimal Basis Iterative Stockholder (MBIS) charge
18

             ------------ Calculation of RESP charges ------------
 -1 Load list of conformer and weights from external file
 0 Return
 1 Start standard two-stage RESP fitting calculation
 2 Start one-stage ESP fitting calculation with constraints
 3 Set method and parameters for distributing fitting points, current: MK
 4 Set hyperbolic penalty and various other running parameters
 5 Set equivalence constraint in fitting, current: H in CH2 and CH3
 6 Set charge constraint in fitting, current: No constraint
 7 Set the way of determining connectivity, current: Guess from bond length
 8 Toggle if loading fitting points and ESP values from Gaussian output file of pop=MK/CHELPG task with IOp(6/33=2) during the calculation, current: No
 9 Load additional fitting centers, current: None
 10 Choose the atomic radii used in fitting, current: Automatic
 11 Choose ESP type, current: Nuclear + Electronic
-1
 Input path of the file containing conformer list, e.g. C:\conflist.txt
confs_weights
 There are    5 conformers
 Sum of weights:    1.000000

             ------------ Calculation of RESP charges ------------
-1 Reload list of conformers from external file, current:   5 conformers
 0 Return
 1 Start standard two-stage RESP fitting calculation
 2 Start one-stage ESP fitting calculation with constraints
 3 Set method and parameters for distributing fitting points, current: MK
 4 Set hyperbolic penalty and various other running parameters
 5 Set equivalence constraint in fitting, current: H in CH2 and CH3
 6 Set charge constraint in fitting, current: No constraint
 7 Set the way of determining connectivity, current: Guess from bond length
 8 Toggle if loading fitting points and ESP values from Gaussian output file of pop=MK/CHELPG task with IOp(6/33=2) during the calculation, current: No
 9 Load additional fitting centers, current: None
 10 Choose the atomic radii used in fitting, current: Automatic
 11 Choose ESP type, current: Nuclear + Electronic
5

 Please select options 1~3. You can also use options 10 or 11 to generate file containing equivalence constraint, which can then be utilized by option 1
 Note: For standard two-stage RESP fitting, options 0 and 1 only take effect for the first stage

 0 No equivalence constraint will be imposed
 1 Load equivalence constraint setting from external plain text file
 2 Constraint H in each =CH2, -CH2-, CH3 to be equivalent in one-stage fitting
 10 Export equivalence constraint corresponding to "H in each =CH2, -CH2-, CH3" to eqvcons_H.txt in current folder
 11 Generate equivalence constraint according to point group of global or local geometry and write to eqvcons_PG.txt in current folder
1
 Input path of the plain text file, e.g. C:\eqvcons.txt
 If pressing ENTER button directly, eqvcons.txt in current folder will be loaded
eqvcons.txt
 OK, equivalence constraint will be loaded from it during calculation

             ------------ Calculation of RESP charges ------------
-1 Reload list of conformers from external file, current:   5 conformers
 0 Return
 1 Start standard two-stage RESP fitting calculation
 2 Start one-stage ESP fitting calculation with constraints
 3 Set method and parameters for distributing fitting points, current: MK
 4 Set hyperbolic penalty and various other running parameters
 5 Set equivalence constraint in fitting, current: Customized
 6 Set charge constraint in fitting, current: No constraint
 7 Set the way of determining connectivity, current: Guess from bond length
 8 Toggle if loading fitting points and ESP values from Gaussian output file of pop=MK/CHELPG task with IOp(6/33=2) during the calculation, current: No
 9 Load additional fitting centers, current: None
 10 Choose the atomic radii used in fitting, current: Automatic
 11 Choose ESP type, current: Nuclear + Electronic
1
 Atomic radii used:
 Element:H      vdW radius (Angstrom): 1.200
 Element:C      vdW radius (Angstrom): 1.500
 Element:N      vdW radius (Angstrom): 1.500
 Element:O      vdW radius (Angstrom): 1.400
 Element:P      vdW radius (Angstrom): 1.800
 Generating fitting points and calculate ESP for conformer    1
 Number of MK fitting points used:     23208

 Initializing LIBRETA library (fast version) for ESP evaluation ...
 LIBRETA library has been successfully initialized!

 NOTE: The ESP evaluation code based on LIBRETA library is being used. Please cite Multiwfn original papers (J. Comput. Chem., 33, 580-592 (2012) and J. Chem. Phys., 161, 082503 (2024)) and the paper describing the efficient ESP evaluation algorithm adopted by Multiwfn (Phys. Chem. Chem. Phys., 23, 20323 (2021))

 Progress: [##################################################]   100.0 %     \
 Generating fitting points and calculate ESP for conformer    2
 Number of MK fitting points used:     22932

 Initializing LIBRETA library (fast version) for ESP evaluation ...
 LIBRETA library has been successfully initialized!

 NOTE: The ESP evaluation code based on LIBRETA library is being used. Please cite Multiwfn original papers (J. Comput. Chem., 33, 580-592 (2012) and J. Chem. Phys., 161, 082503 (2024)) and the paper describing the efficient ESP evaluation algorithm adopted by Multiwfn (Phys. Chem. Chem. Phys., 23, 20323 (2021))

 Progress: [##################################################]   100.0 %     /
 Generating fitting points and calculate ESP for conformer    3
 Number of MK fitting points used:     24706

 Initializing LIBRETA library (fast version) for ESP evaluation ...
 LIBRETA library has been successfully initialized!

 NOTE: The ESP evaluation code based on LIBRETA library is being used. Please cite Multiwfn original papers (J. Comput. Chem., 33, 580-592 (2012) and J. Chem. Phys., 161, 082503 (2024)) and the paper describing the efficient ESP evaluation algorithm adopted by Multiwfn (Phys. Chem. Chem. Phys., 23, 20323 (2021))

 Progress: [##################################################]   100.0 %     \
 Generating fitting points and calculate ESP for conformer    4
 Number of MK fitting points used:     23186

 Initializing LIBRETA library (fast version) for ESP evaluation ...
 LIBRETA library has been successfully initialized!

 NOTE: The ESP evaluation code based on LIBRETA library is being used. Please cite Multiwfn original papers (J. Comput. Chem., 33, 580-592 (2012) and J. Chem. Phys., 161, 082503 (2024)) and the paper describing the efficient ESP evaluation algorithm adopted by Multiwfn (Phys. Chem. Chem. Phys., 23, 20323 (2021))

 Progress: [##################################################]   100.0 %     /
 Generating fitting points and calculate ESP for conformer    5
 Number of MK fitting points used:     22904

 Initializing LIBRETA library (fast version) for ESP evaluation ...
 LIBRETA library has been successfully initialized!

 NOTE: The ESP evaluation code based on LIBRETA library is being used. Please cite Multiwfn original papers (J. Comput. Chem., 33, 580-592 (2012) and J. Chem. Phys., 161, 082503 (2024)) and the paper describing the efficient ESP evaluation algorithm adopted by Multiwfn (Phys. Chem. Chem. Phys., 23, 20323 (2021))

 Progress: [##################################################]   100.0 %     \
 Reloading the first file when Multiwfn boots up...

 No charge constraint is imposed in this stage
 Loading equivalence constraint setting from eqvcons.txt
 Atom equivalence constraint imposed in this fitting stage:
 Constraint   1:   14(O )   18(O )
 Constraint   2:   15(O )   19(O )
 Constraint   3:   16(O )   20(O )   24(O )
 Constraint   4:   32(H )   33(H )

 **** Stage 1: RESP fitting under weak hyperbolic penalty
 Convergence criterion:  0.0000010000
 Hyperbolic restraint strength (a): 0.000500    Tightness (b): 0.100000
 Iter:   1   Maximum charge variation:    1.5077332405
 Iter:   2   Maximum charge variation:    0.1107636558
 Iter:   3   Maximum charge variation:    0.0039944874
 Iter:   4   Maximum charge variation:    0.0001558212
 Iter:   5   Maximum charge variation:    0.0000063158
 Iter:   6   Maximum charge variation:    0.0000002668
 Successfully converged!

 **** Stage 2: RESP fitting under strong hyperbolic penalty
 Atom equivalence constraint imposed in this fitting stage:
 Constraint   1:   32(H )   33(H )
 Fitting objects: sp3 carbons, methyl carbons and hydrogens attached to them
 Indices of these atoms:
    4C    32H    33H     6C    34H     8C    35H    10C    36H    12C
   37H
 Convergence criterion:  0.0000010000
 Hyperbolic restraint strength (a): 0.001000    Tightness (b): 0.100000
 Iter:   1   Maximum charge variation:    1.5345257854
 Iter:   2   Maximum charge variation:    0.0125232048
 Iter:   3   Maximum charge variation:    0.0001932288
 Iter:   4   Maximum charge variation:    0.0000027221
 Iter:   5   Maximum charge variation:    0.0000000376
 Successfully converged!

   Center       Charge
     1(P )   1.4135630800
     2(P )   1.4241920085
     3(P )   1.3536680793
     4(C )   0.3760715582
     5(O )  -0.6307782017
     6(C )   0.2527058666
     7(O )  -0.7174906128
     8(C )   0.6780984537
     9(O )  -0.9591365413
    10(C )   0.1435696375
    11(O )  -0.9245005823
    12(C )   0.8770431354
    13(N )  -1.0284259720
    14(O )  -0.8952224744
    15(O )  -0.8323241779
    16(O )  -0.9465635221
    17(C )   0.5937863633
    18(O )  -0.8952224744
    19(O )  -0.8323241779
    20(O )  -0.9465635221
    21(N )  -0.7645206376
    22(O )  -0.6580604115
    23(O )  -0.5547605926
    24(O )  -0.9465635221
    25(C )   0.7500835753
    26(C )  -0.4617961113
    27(C )   1.4542593076
    28(N )  -1.5345257854
    29(N )  -0.6146215415
    30(C )   0.6056978690
    31(N )  -0.6829891638
    32(H )  -0.0477356295
    33(H )  -0.0477356295
    34(H )  -0.0545910770
    35(H )  -0.1429844986
    36(H )   0.0232647432
    37(H )  -0.1020603051
    38(H )   0.0253107478
    39(H )   0.0229862788
    40(H )   0.5191095206
    41(H )   0.5865250363
    42(H )   0.5380987896
    43(H )   0.5834631134
 Sum of charges:  -4.0000000000
 Conformer:    1   RMSE:    0.004924   RRMSE:    0.012598
 Conformer:    2   RMSE:    0.005126   RRMSE:    0.013223
 Conformer:    3   RMSE:    0.007300   RRMSE:    0.019247
 Conformer:    4   RMSE:    0.005913   RRMSE:    0.014901
 Conformer:    5   RMSE:    0.008026   RRMSE:    0.020533
 Weighted RMSE:    0.005650   Weighted RRMSE    0.014530

 Note: Because present calculation involves multiple conformers, the result cannot be exported to .chg file

So I still believe Multiwfn was not fully configurated on your system. I also provide relevant settings in my ~/.bashrc file here:

ulimit -s unlimited
export OMP_STACKSIZE=200M
export PATH=$PATH:/sob/Multiwfn_xxx_bin_Linux
export Multiwfnpath=/sob/Multiwfn_xxx_bin_Linux

Best regards,

Tian

Reasonableness of wB97XD for wavefunction analyses

dummy@example.com (sobereva) — Fri, 12 Jun 2026 22:42:00 +0000

A Multiwfn user asked me if wB97XD is suitable for calculation of delocalization index using Multiwfn and its comparison with GGA and hybrid-GGA functionals. My reply is also provided here, which may be also useful for other Multiwfn users.

---------
wB97XD is a very reasonable choice. Its improvement of representation of wavefunction over (meta-)GGA and common hybrid (meta-)GGA depends on the specific functional and the system.

When a (meta-)(hybrid-)GGA shows evident delocalization error (also known as self-interaction error, SIE) for a system, the improvement of wB97XD is significant. Representative examples include [18]annulene and cyclo[18]carbon. In Angew. Chem. Int. Ed. 2004, 43, 4200–4206, it is shown that B3LYP (20% global HF component) cannot give reasonable structure of [18]annulene, while I found the geometry optimized by wB97XD is fully correct. cyclo[18]carbon cannot be reasonably represented by any functional with insufficient HF composition at long-range, e.g. B3LYP (20% HF) and PBE0 (25% HF), while BHandHLYP (50% HF), M06-2X (54% HF) and wB97XD (22.2% to 100% HF from short-range limit to long-range limit) work reasonably, see my study and review about this system: Carbon, 165, 468-475 (2020), Acc. Mater. Res., 6, 1220−1231 (2025).

(hybrid-)(meta-)GGA functionals with insufficient HF composition at long-range tend to severely overestimate electronic delocalization of the aforemention systems, not only the resulting wavefunction is not reasonable, but also the optimized geometry is qualitatively wrong (strong tendency towards planarization and bond length equalization). For more information about the poor performance of these functionals, see review about delocalization error: WIREs Comput Mol Sci. 2022;e1631.

Transition Dipole Moments analysis

dummy@example.com (sobereva) — Tue, 09 Jun 2026 22:40:25 +0000

ananta wrote:

Dear wsoulie,
I learned from the above email that you are calculating g_lum. I think i can get some help from you. I am trying the 18 then 5 option. I am providing the td-dft output file (done for the triplet 1 state ), now after entering 5 , it is asking for the Multiplicity 1 or 3 , which one should i choose and how should i proceed and how will I get the data about my t1 to s0 transition dipole moments.
Thank you

Assume you are a Gaussian user and you used 50-50 option in TD keyword, then singlet and triplet excited states are all calculated, so Multiwfn asks you to choose the spin multiplicity of the excited state of interest. As you are only interested in T1, you should choose spin multiplicity of 3 in Multiwfn.

Multiwfn MK RESP calculations

dummy@example.com (sobereva) — Thu, 04 Jun 2026 23:54:57 +0000

I am not a MCPB.py user, what I can answer is the way of using Multiwfn to calculate RESP charge.
I don't well understand your question. After loading a wavefunction file into Multiwfn, inputting 7 then 18 then 1 is the most straightforward way of calculating the RESP charge in common sense.

When calculating MK charges or RESP charges based on MK fitting points, different programs may use different density of fitting points and different atom radius for Zn (its radius was not directly defined in the original paper of MK method), the resulting charges may be notably different in some cases. The implementation of RESP charge calculation in Multiwfn is in a very reasonable way.

Zimmerman's Intermediate Localization (almost-canonical orbitals)

dummy@example.com (sobereva) — Fri, 29 May 2026 01:19:50 +0000

I didn't notice this paper before and temporarily don't have adequate time to carefully look into it. Multiwfn is not only able to generate localized molecular orbitals, but also as AdNDP orbitals (may also be viewed as intermediate localized orbitals. see Section 3.17 of Multiwfn manual), and yield their physically meaningful energies (in terms of expectation of Fock or KS operator).

Integrating with mixed type grid

dummy@example.com (sobereva) — Wed, 27 May 2026 19:07:16 +0000

Hello,

Your modification on the code is correct.

PS: A more elegant way is adding your function as a new real space function in functions.f90, and link it into user-defined function ("function userfunc(x,y,z)"); in your function code simply set the returned value to zero if it is found to be >=0.5. In this case you can integrate your function in basin analysis module in terms of integrating user-defined function, any modification of basin.f90 is not needed.

MESP Scan

dummy@example.com (alexlester1996) — Wed, 27 May 2026 03:40:05 +0000

Dear Professor Tian,
I am very grateful to you for your help!
Best regards,
Alex

Energy implementation of the ETS-NOCV analysis

dummy@example.com (sobereva) — Tue, 26 May 2026 17:43:58 +0000

I think this output is easy to understand. It is just the contribution of various angular moments to the NOCV orbitals and pair, so that you can better undstand its nature (Similar to the orbital composition analysis illustrated in Section 4.8 of Multiwfn manual).

Incorrect atoms labeling in CPprop.txt

dummy@example.com (joshuabohr) — Fri, 22 May 2026 10:44:59 +0000

OK, thank you so much for your quick reply and for your help!

Calculating Electric Quadrupole Moments Between Excited States

dummy@example.com (akramer) — Wed, 20 May 2026 22:39:06 +0000

Dear Dr. Tian,
Thank you for your kind and thorough response! I will modify the source code as you have suggested to create this utility. Once again I appreciate your fast response and your in-depth description of suggested modifications.

Best,
Augusta

plane.txt with gnuplot

dummy@example.com (sobereva) — Sat, 16 May 2026 08:11:05 +0000

Hello,

The plane.txt exported by Multiwfn can be directly imported into e.g. Sigmaplot to plot plane map. I doesn't have any experience in plotting plane map by gnuplot based on external plane data. The meaning of each column of plane.txt is clearly described on screen when Multiwfn exports it, you may consider to write a script to convert the format according to the requirement of the plotting tool you want to use.

Aromaticity index calculation

dummy@example.com (alessiomacorano) — Wed, 13 May 2026 13:56:41 +0000

Dear Prof Tian Lu,

Simply Amazing!! thank you so much for your detailed response !!

My best

Alessio