My Quantum Chemistry(version:demo)

Overview

My Quantum Chemistry(MQC) is an open-source package based on Ab-initio Quantum Chemistry(mainly) methods.This package aims to provide a simple and convenient platform for quickly implementing new theoretical methods, which also can be a teaching tool (toy model) for beginners to learn Quantum Chemistry.

MQC is based on Fortran90. To maintain the readability,code is not parallel in principle,and should be consistent with formulas as much as possible. As a result,the efficiency may be low,but will remain within an acceptable range.

Installation

MQC can run on Linux and Windows platforms and used some linear algebra libraries,like BLAS LAPACK ,so you need to configure these environments before using it.

The package provides dynamic linked library (libblas.dll and liblapack.dll) of LAPACK 3.11 compiled by gfortan 8.1.0(MinGW) for Windows and static library(librefblas.a and libreflapack.a) compiled by gfortan 11.3.0 for Linux in the lapack folder.

There are two ways to use MQC

1.Compile from source code

You need fortran compiler,both gfortran and ifort are acceptable. Using Makefile can easily compile binary files,but you should make sure that the LAPACK or MKL was added to environment variables. You can also specify the library directory by yourself.

To install the package,you need to first enter the directory where the source code is located and execute the following command in the terminal:

for Windows

make

for Linux

make mqclinux

then you can get the binary file mqc. You can use the following command to clean the auxiliary files:

for Windows

make clean

for Linux

make cleanlinux

Done!

2.Directly use the precompiled binary file

You can get the precompiled binary file mqc from github release.

Quickstart

The running mode of mqc is mqc +input file path,default to the same path as mqc binary file.

For example, mqc .\INPUT.inp is the same as mqc.

You need to prepare your input file INPUT.inp following this type firstly.

The structure of input file has the following forms :

INPUT title
! System
# Block name 1
  keyword11 option11
  keyword12 option12
  ...
END  
# Block name 2
  keyword21 option21
  ...
END  
...
# MOLECULE  
  Charge   Spin-multiplicity
  Unit name
  Num of atoms
  Z(atomic number which must be interger)         Coordinates( X       Y       Z)
END
...
Other blocks
...
> END

All the keywords are either all uppercase or all lowercase .

Consider that you want to calculate the electronic energy of a $H_2O$ molecule.

Hello water !
! WINDOWS
# TASK
  ENERGY  HF
END
# BASIS
  STO-3G
END
# MOLECULE 
  0 1
  BOHR
  3
  8   0.0000000000      0.0000000000      0.0000000000
  1   0.0000000000      0.0000000000      2.0579117598
  1   1.9923609397      0.0000000000     -0.5152602865
END
>END

Keep the input fileINPUT.inp and the binary file mqc in the same directory,then run mqc. Done!

For more specific content, please refer to the document.

Package Features

• Integral
  • Overlap integrals (S)
  • Kinetic integrals (T)
  • Nuclear attraction integrals (NAI)
  • Electron-electron repulsion integrals (ERI)
• Single Point Energy
  • Restricted-Hartree-Fock (RHF)
  • Møller–Plesset perturbation theory (MP2,MP2.5,MP3)
  • Coupled cluster singles and doubles (CCSD)
  • CCSD with perturbative triples correction CCSD(T)
• Wavefunction Analysis and Property
  • Mulliken charges
  • Löwdin charges
  • dipole moment

Document

It is easy to generate document of MQC. The Doc folder is a sphnix project. You can use the following command to generate html or $latex$ project of document.

make html

make latex

You can use make cleandoc to clean up the document files. See how to generate document.

Reference

[1] Programming Projects from Crawford Group [2] Q. Sun. J. Comput. Chem. 2015, 36, 1664–1671. DOI: 10.1002/jcc.23981