New Software Release: SIESTA 5.0

16 May 2024

The SIESTA team proudly announces the release of SIESTA 5.0

SIESTA is both a method and its computer program implementation, to perform efficient electronic structure calculations and ab initio molecular dynamics simulations of molecules and solids within Density Functional Theory (DFT). The efficiency of SIESTA stems from the use of a basis set of strictly-localized atomic orbitals. A very important feature of the code is that its accuracy and cost can be tuned in a wide range, from quick exploratory calculations to highly accurate simulations matching the quality of other approaches, such as plane-wave methods. SIESTA also offers the TranSIESTA method, based on the non-equilibrium Green’s functions formalism, and enabling open-boundary condition calculations, including simulations under bias.

The possibility of treating large systems with first-principles electronic-structure methods has opened up new opportunities in many disciplines. The SIESTA program is open source and has become quite popular, being increasingly used by researchers in geosciences, biology, and engineering (apart from those in its natural habitat of materials physics and chemistry). Currently there are several thousand users all over the world, and the original paper describing the method (J. Phys. Cond. Matt. 14, 2745 (2002)) has received more than 11,000 citations so far.

SIESTA 5.0 introduces new functionalities to further support the community’s needs. Key new features include:

• New CMake-based building framework, with support for dependency handling and tests, which will facilitate future integrations.
• A new implementation of Real-Time TDDFT.
• Full spin-orbit coupling capabilities, including compatibility with the DFT+U scheme.
• Support for D3 dispersion corrections, via the simple-DFTD3 library.
• Support for PSML pseudopotential files, thus enabling the use of databases of curated pseudopotentials such as Pseudo-Dojo.
• New “wrapper-library” interface to Wannier90, allowing SIESTA to call it on-the-fly.
• Internal units standardization, compatible with CODATA-2018.
• Updated basis-set generation code and upgraded default settings.
• New and updated versions for Conda binaries and Spack recipes.

For a more comprehensive overview of what’s new, read the SIESTA 5.0.0 Release Notes. To get the code, please visit the SIESTA Code Access page.

SIESTA development model and funding

SIESTA is the result of the collaborative effort of dozens of developers, working within the open-source model. A list of contributors, as well as the composition of the core curating and steering teams, can be found here.

The development of SIESTA has been funded over the years by the national Spanish research agencies. The latest cycle of funding comprises a coordinated project with six nodes (ICMAB-CSIC, ICN2, CIC nanoGUNE, University of Cantabria, Autonomous University of Madrid, and ICMM-CSIC), with grant numbers PID2022-139776NB-C61 to PID2022-139776NB-C66 of the Spanish MCIN/AEI/10.13039/501100011033, also supported by the ERDF, A way of making Europe.

SIESTA is also one of the lighthouse codes of MaX “MAterials design at the eXascale”, a Centre of Excellence co-funded by the European High Performance Computing Joint Undertaking (EuroHPC JU) under grant agreement No. 101093374 and grants PCI2022-134972-2, PCI2022-134978-2 and PCI2022-135083-2 funded by the Spanish MICIU/AEI/10.13039/501100011033 and European Union NextGenerationEU/PRTR. MaX aims at deploying its flagship codes on the new and upcoming (pre-)exascale supercomputers so that they can be efficiently used by the materials science research community. The MaX nodes involved in the development of SIESTA are ICN2, ICMAB-CSIC, and BSC-CNS.