Multiwfn forum

sobereva

Tian Lu (Multiwfn developer)

From: Beijing

Registered: 2017-09-11

Posts: 1,622

Website

ORCA to Multiwfn

A post appears in ORCA forum today (https://orcaforum.cec.mpg.de/viewtopic.php?f=8&t=4034), I copy it here because some users may also have the same question

Hello, I am new to computational chemistry and I have little clue what I am doing, but first of all I want to make sure I am using ORCA correctly since I am using it on windows.
I use WebMO as the interface, and I was trying to use the BL3YP/6-31G(d,p), but on the webMO interface, there was no such option, but I selected B3LYP, and typed 6-31(d,p), and ORCA returned:

"Your calculation utilizes the basis: 6-31G(d,p)", somewhere in the output text file. So I hope the calculations were indeed done using this basis set!

Anyways, my question: I have been using ORCA and I was wondering if the ORCA software can export out a wavefunction file for direct use in MultiWFN. --- https://sites.google.com/site/orcainput ... y-analysis
This site discussed potential of MultiWFN with ORCA, and it says for to output ORCA into MultiWFN, ""Requires creation of a Molden file: orca_2mkl file -molden"".

However the function I perform on MultiWFN requires a wavefunction (.wfn) file. So I have little clue how to do it. Currently, I have been reading the ORCA outputs on a textfile in webMO.

Thank you so much in advance if you know how to do it.

Below is my reply

I am developer of Multiwfn. For ORCA users, I strongly recommend to directly use the Molden input file generated by orca_2mkl instead of the .wfn file generated by orca_2aim. Because .molden file can provide basis function information for Multiwfn, and consequently, almost all analysis functions in Multiwfn could be used. However, if .wfn is employed, only the analyses based on real space functions can be used. Please check Section 2.6 of Multiwfn manual for more information.

For present version of Multiwfn, you do not need to manually change the .molden.input suffix to .molden, since currently Multiwfn automatically recognizes any file with .molden or .molden.input as Molden input file.

Current version of Multiwfn supports the Molden input file generated by ORCA up to g angular moment. Currently Molden input file with h angular moment is not supported by Multiwfn since the h is also not formally supported by standard Molden input format.

When file suffix is unknown to Multiwfn, Multiwfn automatically treats the file as a plain text file, and no data will be loaded from it when Multiwfn boots up. In version 3.3.7, .molden.input suffix has not been supported. While in present version, all .molden, .molden.input and .molden.inp are recognized as Molden input file, as shown in Section 2.5 of the manual.