Hacktoberfest 2026: the issues maintainers tagged for October, open and beginner-friendly. Browse Hacktoberfest issues

Builder: open and save CIF files (unit cell from symmetry operations)

Open
#358 0 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
28/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Active
Tech stack
c
Domain
data

Research direction

Start with the Builder’s existing periodic-cell import paths and the space-group tables it already uses; the payload names PDB (CRYST1), .gro, and .car as examples. The design brief is ready, but this work is scheduled after the GROMACS run settings and end-to-end clay system. Done means CIF import and P1 export round-trip, with the listed structures verified against Open Babel and Z × formula.

Written by the indexing model from the issue text.

Description

The Builder cannot open CIF files, which is how crystal structures come from the databases (COD, AMCSD, Materials Project, the IZA zeolite database). PDB (CRYST1), .gro and .car already bring their cell.

Scope:

  • Import: cell, _atom_site_ loop, symmetry operations as listed (or, when only a space-group name is given, the space-group tables the Periodic Builder already uses), duplicates at special positions removed by periodic distance, result in the cell at 1×1×1.
  • Partial occupancy: the majority species on each site, with a warning listing the sites. A warning when hydrogens are absent (common in mineral CIFs).
  • Export: P1 CIF of the current periodic structure; export → import round trip.
  • Verification against Open Babel (--fillUC strict) and against Z × formula, for pyrophyllite (Lee & Guggenheim 1981), quartz, graphite, NaCl, LiCoO₂, a zeolite, and a CIF with a space-group name only.

A design brief is ready; to be done after the GROMACS run settings and the end-to-end clay system.

Dominant language
C
Stars
10
Forks
8
Avg merge
21m
Merged PRs (30d)
1

Getting set up

This project ships no dev container, Dockerfile or contributing guide, so setting up is up to you: start from its README, and see our first-contribution guide for the general steps.

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

More from FriendsofECCE/ECCE

All issues in FriendsofECCE/ECCE

Similar issues

More C issues

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.