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Multiwfn - a Multifunctional Wavefunction Analyzer

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Multiwfn - a Multifunctional Wavefunction Analyzer Multiwfn - A Multifunctional Wavefunction Analyzer - Software Manual with abundant tutorials and examples in Chapter 4 Version 3.3.8 2015-Dec-1 http://Multiwfn.codeplex.com Tian Lu [email protected] Beijing Kein Research Center for Natural Sciences (www.keinsci.com) !!!!!!!!!! ALL USERS MUST READ !!!!!!!!!! I know, most people, including myself, are unwilling to read lengthy manual. Since Multiwfn is a heuristic and very user-friendly program, it is absolutely unnecessary to read through the whole manual before using it. However, you should never skip reading following content! 1. The BEST way to get started quickly is directly reading Chapter 1 and the tutorials in Chapter 4. After that if you want to learn more about Multiwfn, then read Chapters 2 and 3. Note that the tutorials and examples given in Chapter 4 only cover the most frequently used functions of Multiwfn. Some application skills are described in Chapter 5, which may be useful for you. 2. Different functions of Multiwfn require different type of input file, please read Section 2.5 for explanation. 3. If you do not know how to copy the output of Multiwfn from command-line window to a plain text file, consult Section 5.4. If you do not know how to enlarge screen buffer size of command-line window of Windows system, consult Section 5.5. 4. If the error “No executable for file l1.exe” appears in screen when Multiwfn is invoking Gaussian, you should set up Gaussian environment variable first. For Windows version, you can refer Appendix 1. (Note: Most functions in Multiwfn DO NOT require Gaussian installed on your local machine) 5. The so-called ”current directory” in this manual is the path where you are invoking Multiwfn. If you boot up Multiwfn by clicking the icon of executable file in Windows, the “current directory” is the position of the executable file. For the case of command-line mode, if you are in “D:\study\” directory when invoking Multiwfn, then “D:\study\” is “current directory”. 6. Please often check Multiwfn website and update the program to the latest version. Multiwfn is always in active development, useful functions are continuously added, bugs are continuously fixed and efficiency is constantly improved. 7. Please feel free to ask any question about using Multiwfn by emailing me ([email protected]), but please ensure that you have read this manual carefully to find solution, and you have updated your Multiwfn to the latest version. I would like to provide as much help as I can for any Multiwfn user. \()/ i Linux and Mac OS X USERS MUST READ 1. See Section 2.1.2 and 2.1.3 on how to install Linux and Mac OS X versions of Multiwfn, respectively. 2. I cannot guarantee that Linux and Mac OS X versions are as robust as Windows version, since all of my developments and most debugging are performed in Windows environment. Windows version is more recommended to be used, especially for beginners. There is no evident difference in calculation speed between prebuilt Windows, Linux and Mac OS X versions, since they are both compiled by Intel FORTRAN compiler with similar options. Besides, due to some unsolved bugs of Linux and Mac OS X version of DISLIN graphical library, a few visualization functions of Multiwfn are limited, see below. 3. When graphical user interface (GUI) appears, the graph will not be shown automatically, you have to do something to active the graph first, e.g. clicking "up" button or dragging a scale bar on GUI. 4. If you would like to view the isosurface of just generated grid data in Multiwfn, you have to make sure that the number of grid points in x,y,z directions are identical, e.g. 80*80*80. So, do not choose 1, 2 or 3 in grid setting stage (namely low/middle/high quality grid) if you want to view isosurface in Multiwfn, because in these three modes Multiwfn will determine grid points in each directions automatically according to molecule size. 5. Transparent style does not work when showing isosurfaces in GUI window. But if you choose to save the picture, the transparent isosurfaces will be rendered normally in the resulting graphical file. ii About the manual This manual is organized as following sequence: Chapter 1 Overview: Briefly describes what is Multiwfn and what Multiwfn can do. Chapter 2 General information: Introduces all aspects beyond specific functions of Multiwfn, such as how to install, how to use, supported file types, etc. Chapter 3 Functions: Describes all functions and related theories of Multiwfn in detail. Chapter 4 Tutorials and examples: Plenty of practical examples are provided for helping users to use Multiwfn. Chapter 5 Skills: Some useful skills in using Multiwfn. Appendix In general, italics font is used for input commands and journal name throughout this manual. Very important contents are highlighted by red color. You can directly jump to specific section by choosing corresponding entry in bookmark window of your pdf reader. The purpose of this manual is not only helping users to use Multiwfn, but also introducing related theories. I hope any quantum chemist can benefit from this manual. Albeit I have tried to write this manual as readable as possible for beginners, some topics request the readers have basic knowledges of quantum chemistry. If the readers have carefully read the book "Quantum Chemistry 7ed" written by Ira. Levine, then they will never encounter any difficulty during reading through the whole manual. iii Content !!!!!!!!!! ALL USERS MUST READ !!!!!!!!!! ......................................... i Linux and Mac OS X USERS MUST READ ........................................ ii About the manual.................................................................................... iii 1 Overview...............................................................................................1 2 General information............................................................................6 2.1 Install.......................................................................................................................................6 2.1.1 Windows version..............................................................................................................6 2.1.2 Linux version ...................................................................................................................6 2.1.3 Mac OS X version............................................................................................................7 2.2 Using Multiwfn.......................................................................................................................7 2.3 The files of Multiwfn ..............................................................................................................8 2.4 Parallel implementation ..........................................................................................................8 2.5 Input files and wavefunction types..........................................................................................8 2.6 Real space functions..............................................................................................................12 2.7 User defined real space function ...........................................................................................23 2.8 Graphic formats and picture size...........................................................................................30 3 Functions ............................................................................................31 3.1 Defining molecular fragment (-3, -4)....................................................................................31 3.2 Showing molecular structure and viewing orbitals / isosurfaces (0).....................................31 3.3 Outputting all properties at a point (1)..................................................................................33 3.4 Outputting and plotting specific property in a line (3)..........................................................34 3.5 Outputting and plotting specific property in a plane (4) .......................................................35 3.5.1 Graph types ....................................................................................................................35 3.5.2 Setting up grid, plane and plotting region ......................................................................39 3.5.3 Options in post-process interface ...................................................................................41 3.5.4 Setting up contour lines..................................................................................................41 3.5.5 Plot critical points, paths and interbasin paths on plane graph.......................................42 3.6 Outputting and plotting specific property within a spatial region (5) ...................................44 3.7 Custom operation, promolecular and deformation properties (subfunction 0, -1, -2 in main function 3, 4, 5)...........................................................................................................................47 3.7.1 Custom operation for multiple wavefunctions (0) .........................................................47 3.7.2 Promolecular and deformation properties (-1, -2)..........................................................47 3.7.3 Generation of atomic wavefunctions..............................................................................48 3.7.4 Sphericalization of atom wavefunction..........................................................................49 iv 3.8 Checking & Modifying
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