6. Online utilities

We have created a number of useful online utilities, which can be used for preparing USPEX input and for post-processing. The utilities are available at:

https://uspex-team.org/online_utilities/

Below you can find information about each one of them.

6.1. Structure characterization

Here we have 5 utilities:

  • Fingerprints — the utility calculates and plots fingerprint function, which is a crystal structure descriptor, a 1D-function related to the pair correlation function and diffraction patterns. It does not depend on absolute atomic coordinates, but only on interatomic distances. Small deviations in atomic positions will influence the fingerprint only slightly, i.e. it is numerically robust.

  • Multifingerprint — the utility calculates average quasi-entropy, A-order(average atomic order parameter) and S-order(whole-structure order parameter) for a set of structures. Also it filters unique structures by cosine distances difference \(\geq\) 0.003, identifies the symmetry of these structures and lists them in the uniq_gatheredPOSCARS file.

  • POSCAR2CIF — determines space group and prepares a CIF file from a POSCAR file.

  • CIF2POSCAR — prepares a POSCAR file from a CIF file.

  • XSF2POSCAR — prepares a POSCAR file from a XCRYSDEN file.

6.2. Properties calculations

Here we have 2 utilities:

  • Hardness — the utility is to calculate hardness based on the Mazhnik-Oganov model.

  • EELS — the utility calculates the Electron Energy Loss Spectrum (EELS). Written by Priya Johari.

6.3. Molecular crystals

Here we have 2 utilities:

  • MOL precheck — the utility allows you to check files before running USPEX for molecular crystals.

  • Zmatrix — the utility converts file to USPEX file.

6.4. Surfaces

Substrate — a program which prepares a substrate from a POSCAR/CIF file, given Miller indices, thickness of the layer, and shift. The resulting POSCAR file can be used for as a substrate for surface calculations ( dim=2 ).

6.5. Miscellaneous

Here we have the following:

  • Input generator — USPEX input.uspex generator. The utility can help beginners to create a correct input for USPEX calculations.

  • Volume estimation — the utility estimates volumes of non-molecular and molecular crystals for USPEX (for input.uspex file).

  • USPEX manual — online version of this manual.

  • USPEX examples — archives with USPEX examples.

  • Pressure-composition phase diagram — This program uses the Linear Approximation of Enthalpy (LAE) to calculate the approximate pressure-composition phase diagram from USPEX results from just one pressure.