SSeTe

ChalMolDB

Chalcogen Molecular Database

Curated electronic-property data on how sulfur, selenium and tellurium tune the band gap of donor–acceptor semiconducting materials. Every value keeps its source and level of theory.

Open the database ↗ Watch the 75-second tour DOI 10.5281/zenodo.23558298
5,029curated records
4,229unique structures
1,371experimental band gaps
4,2113D structures
Product tour

See it in 75 seconds

  • Filter and search 5,029 records by collection, chalcogen, gap or source
  • Inspect a record: computed and measured gaps side by side, with method and 3D geometry
  • Draw a structure and search by exact match, substructure or similarity
Database v1.2

Four collections, one identity layer

Source records and standardized structures are kept apart, so the same molecule reported in several studies stays traceable to each of them. Values from different levels of theory are never pooled.

3,088

Development

Donor–acceptor molecules with exact structures and 3D coordinates.

B3LYP/6-311+G(d)
400

External

Chalcogen oligomer series from monomer to extrapolated polymer.

B3LYP · LC-BLYP · PCM
1,323

PolymerNEW

Conjugated polymers with experimental optical gaps and oligomer DFT values.

Experiment · B3LYP-D3/6-31G*
218

LiteratureNEW

Thia-, seleno- and telluro[n]helicenes against CCSD(T), plus Se/Te monomers.

CCSD(T) · 13 functionals
chalmoldb.streamlit.app/?page=database
Database workspace filtered to the 1,323 polymer records
What the combined data shows

Comparisons no single source supports

Bringing the collections together makes it possible to test chalcogen effects against experiment and against high-level reference gaps.

84%

Selenium lowers the measured gap

In 139 polymer pairs that differ only by S→Se substitution, the experimental optical gap dropped in 84% of cases (mean −0.05 eV). Oligomer DFT shows the same direction in 90%.

Experimental gap lower with Se 117 of 139 pairs DFT gap lower with Se 90%
Experimental data: Nagasawa et al. 2018 · oligomer DFT: Liu et al. 2025
S → Te

Functional errors grow with the chalcogen

Mean absolute error of the DFT HOMO–LUMO gap against the CCSD(T) fundamental gap, chalcogen [n]helicenes.

B3LYPPBE0CAM-B3LYP 3.43 · 3.66 · 3.80 eV1.25 · 1.54 · 1.690.88 · 1.15 · 1.35 SSeTe
Data: Kumar, Kar & Maity, J. Comput. Chem. 2025
Open data

Use it in your own work

The full release is distributed as versioned files with SHA-256 checksums. No account or API key is needed.

RecordsCSV · 5,029 rows
3D structuresSDF · 4,211 geometries
LicencesData CC BY 4.0 · code MIT
Source codeGitHub
import pandas as pd

BASE = ("https://raw.githubusercontent.com/"
        "EsraDogan539/molecular-descriptor-platform/main/")
records = pd.read_csv(BASE + "data/public/chalmoldb_records.csv")

# tellurium systems with an exact structure
te = records[(records.Te_Count > 0) & records.InChIKey.notna()]
How to cite

Cite the release you used

Doğan, E. N.; Kayı, H. ChalMolDB: Chalcogen Molecular Database, Database v1.2. Zenodo, 2026.

https://doi.org/10.5281/zenodo.23558298

The concept DOI 10.5281/zenodo.22903549 covers all versions. A journal article describing ChalMolDB is under review.

Team

Department of Chemical Engineering, Ankara University

Esra Nur Doğan

PhD researcher

Database design, data curation and software development.

ORCID 0000-0001-5755-7596

Prof. Dr. Hakan Kayı

Supervisor · corresponding author

Scientific supervision; computational chalcogen studies behind the external collection.

ORCID 0000-0001-7300-0325 · hkayi@ankara.edu.tr