rust-libcint

Provide wrappers for libcint (C)

lib.rs:

rust-libcint

The rust-libcint crate provides wrappers for libcint (C).

In order to use the crate, the libcint should be installed with the outcome library libcint.so stored in a reachable path by users.

Please visit https://github.com/sunqm/libcint for more details about the installation and the usage of libcint

The CINTR2CDATA struct groups all necessary data for using libcint. Various kinds of analytical Gaussian-type orbital (GTO) integrals provided by libcint are then wrapped as the methods defined on the CINTR2CDATA struct.

Currently, only four kinds of integrals, including 1) the one-electron kinetic integral, 2) the one-electron nuclear attractive integral, 3) the one-electron overlap integral, and 4) the two-electron repulsive integral are available for both spheric and Cartesian GTOs. The other kinds of integrals are not yet ready in the current version.

Examples

//=============================================================================
// Prepare `atm`, `bas` and `env` with the same data structures of those used by `libcint`.
// Refer to <https://github.com/sunqm/libcint/blob/master/doc/program_ref.pdf> 
// for the details of these data structures.
//=============================================================================
use rust_libcint::{CINTR2CDATA,CintType};
let mut atm: Vec<Vec<i32>> = vec![];
atm.push(vec![2,0,0,0,0,0]);
atm.push(vec![4,3,0,0,0,0]);
let mut natm = atm.len() as i32;
let mut bas: Vec<Vec<i32>> = vec![];
bas.push(vec![0,1,1,1,1,6,7,0]);
bas.push(vec![0,2,1,1,1,8,9,0]);
let mut nbas = bas.len() as i32;
let mut env: Vec<f64> = vec![0.0,0.0,0.0,0.7,0.0,0.0,1.0,1.0,0.5,1.0];
let mut cint_data = CINTR2CDATA::new();
// Transfer `atm`, `bas`, and `env` to the raw pointers,
// and organize them by the `CINTR2CDATA` structure.
cint_data.initial_r2c(&atm,natm,&bas,nbas,env);
//=============================================================================
//The 2-electron repulsive integrals (ERIs) for spheric Gaussian-type orbitals
//=============================================================================
// The GTO functions considered here are shperic.
// For Cartesian GTOs, replace `CintType::Spheric` by 
//  `CintType::Cartesian` on the following line:
cint_data.set_cint_type(CintType::Spheric);
cint_data.cint2e_optimizer_rust();
let buf = cint_data.cint_ijkl(0,1,1,0);
let mut v1:f64=0.0;
&buf.into_iter().for_each(|i| {v1 += i.abs()});
println!("The reference data for cint2e ERIs: 0.5745411555937561; v1: {:18.16}; ",v1);
//=============================================================================
//The one-electron overlap integrals for spheric Gaussian-type orbitals
//=============================================================================
cint_data.cint_del_optimizer_rust();
// The GTO functions considered here are shperic
cint_data.set_cint_type(CintType::Spheric);
cint_data.cint1e_ovlp_optimizer_rust();
let buf = cint_data.cint_ijovlp(0,1);
let mut v1:f64=0.0;
&buf.into_iter().for_each(|i| {v1 += i.abs()});
println!("The reference data for cint1e_ovlp: 0.7096366827378776; v1: {:18.16}; ",v1);
//=============================================================================
//The one-electron kinetic integrals for Cartesian Gaussian-type orbitals
//=============================================================================
cint_data.cint_del_optimizer_rust();
// The GTO functions considered here are Cartesian
cint_data.set_cint_type(CintType::Cartesian);
cint_data.cint1e_kin_optimizer_rust();
let buf = cint_data.cint_ijkin(0,1);
let mut v1:f64=0.0;
&buf.into_iter().for_each(|i| {v1 += i.abs()});
println!("The reference data for cint1e_kin : 1.5780816190296618; v1: {:18.16}; ",v1);
//=============================================================================
//The one-electron nuclear attraction integrals for Cartesian Gaussian-type orbitals
//=============================================================================
cint_data.cint_del_optimizer_rust();
// The GTO functions considered here are Cartesian
cint_data.set_cint_type(CintType::Cartesian);
cint_data.cint1e_nuc_optimizer_rust();
let buf = cint_data.cint_ijnuc(0,1);
let mut v1:f64=0.0;
&buf.into_iter().for_each(|i| {v1 += i.abs()});
println!("The reference data for cint1e_nuc : 4.0007622494430706; v1: {:18.16}; ",v1);
//=============================================================================
// Finally deallocate the memory by transferring the raw pointers back to RUST
// i.e. Vec::from_raw_parts();
//=============================================================================
cint_data.final_c2r();