BLOCK implements the density matrix renormalization group (DMRG) algorithm for quantum chemistry.
- DMRG-CASSCF: close integration with PySCF (up to about 40 orbitals and 3000 basis functions)
- DMRG-NEVPT2 (up to about 24 orbitals and 1200 basis functions with PySCF)
- DMRG-NEVPT2 with compressed MPS perturber (up to about 30 orbitals and 1200 basis functions through PySCF)
- 1, 2, 3, 4-particle density matrices
- 1, 2-particle transition density matrices
BLOCK requires BLAS, LAPACK and BOOST.
MPI library is needed for distributed-memory parallel compilation.
BLOCK is compiled using the makefile supplied in the distribution.
The following customizations need to be made to the makefile placed in the main directory ./Block.
Choose compilers by specifying,
CXX = g++
For MPI-based parallel execution on distributed-memory machines,
USE_MPI = yes
MPICXX = mpicxx
MPI library must be compiled using the same compiler as for compiling BLOCK.
Intel compiler such as icpc is also supported with approriate compiling flags chosen automatically.
Please note that when choosing your compiler, either GNU or Intel, C++0x/C++11 standards must be appropriately supported,
as BLOCK requires new features for some of the modules (eg, npdm, nevpt2, etc).
Here are our suggested minimum GNU/Intel compiler versions in order for the compiling process to be successful:
- GNU g++: 4.8 or newer,
- or Intel icpc: at least 14.0.1 (2013 SP1 Update 1) or newer.
To enable MKL library,
USE_MKL = yes
And supply MKL and BOOST libraries by giving the locations,
MKLLIB = /opt/intel/composer_xe_2013_sp1.0.080/mkl/lib/intel64/
MKLFLAGS = /opt/intel/composer_xe_2013_sp1.0.080/mkl/include
BOOSTLIB = /lib64/boost_1_55_0/lib/
BOOSTINCLUDE = /lib64/boost_1_55_0/include/
When the makefile is configured, run in the directory ./Block
$./make
The successful compilation generates the executable block.spin_adapted, static and shared DMRG libraries libqcdmrg.a and libqcdmrg.so.
BLOCK can be tested by executing the script in the directory ./Block/dmrg_tests,
$cd dmrg_tests
$./runtest
The tests require Python to be installed on the system.
The standalone serial code can be executed running
$block.spin_adapted input.dat > output.dat
input.dat is the input file and the output of the program is piped into the output file output.dat.
The MPI parallel mode can be called running
$mpirun -np 4 block.spin_adapted input.dat > output.dat
Block is distributed under the GNU GPL license which is reproduced in the file LICENSE.
In addition, Block contains a full copy of the Newmat C++ matrix library by Robert Davies.
We would appreciate if you cite the following papers in publications resulting from the
use of Block:
- G. K.-L. Chan and M. Head-Gordon, J. Chem. Phys. 116, 4462 (2002),
- G. K.-L. Chan, J. Chem. Phys. 120, 3172 (2004),
- D. Ghosh, J. Hachmann, T. Yanai, and G. K.-L. Chan, J. Chem. Phys., 128, 144117 (2008),
- S. Sharma and G. K-.L. Chan, J. Chem. Phys. 136, 124121 (2012).
In addition, a useful list of DMRG references relevant to quantum chemistry can be found in the article above by Sharma and Chan.