This is the offical repository of the crest program developed by the Grimme group in Bonn.

crest is an extension to the xtb program. It functions as an IO based OMP scheduler (i.e., calculations are performed by the xtb program) and tool for the creation and analysation of structure ensembles.

For any installation make sure that you have correctly installed and sourced the xtb program before attempting any calculations with crest.

There are multiple possible ways of installing crest. For building the program from source we recommend the Intel ifort and icc compilers.

Use the statically linked binaries (Intel Compiler 2019.6.324) that can be found at the release page, of this repository. Simply unpack the binary and add it to your PATH variable.

tar -xvzf crest.tgz

The program should be directly executable in most cases.

In the src directory a Makefile can be found to build a statically linked binary. Modify the makefile to your requirements and build the program via

make

For the setup of Cmake see also the Cmake setup page hosted at the xtb repository. Building crest with CMake works with the following chain of commands:

export FC=ifort CC=icc
cmake -B _build_intel -DCMAKE_BUILD_TYPE=Release
make -C _build_intel

To install the crest binaries to /usr/local use (might require sudo)

make -C _build_intel install

For the setup an configuration of meson see also the meson setup page hosted at the xtb repository. The chain of commands to build crest with meson is:

export FC=ifort CC=icc
meson setup _build_intel --prefix=$PWD/_dist
meson install -C _build_intel

When attempting to build with gfortran and gcc, add -Dla_backend=mkl to the meson setup command. Tested with version 10.2 of the GNU compilers.

This repository contains several examples for default applications of crest.

See examples. To test the installation please try to run example 0.

The crest documentation is hosted at read-the-docs.

1. P. Pracht, F. Bohle, S. Grimme, Phys. Chem. Chem. Phys., 2020, 22, 7169-7192. DOI: 10.1039/C9CP06869D

2. S. Grimme, J. Chem. Theory Comput., 2019, 155, 2847-2862. DOI: 10.1021/acs.jctc.9b00143

3. P. Pracht, S. Grimme, Chem. Sci., 2021, 12, 6551-6568. DOI: 10.1039/d1sc00621e

crest is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

crest is distributed in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose. See the GNU Lesser General Public License for more details.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in crest by you, as defined in the GNU Lesser General Public license, shall be licensed as above, without any additional terms or conditions