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Per-space-group entry counts within the Crystallography Open Database's inorganic (no-carbon formula) class, by publication year, 1960-2026 (2026 partial through early August). Harvested from the COD REST API on 2026-08-09: one CSV query per publication year, entries classified as no-carbon by element-token match on the COD formula fields, grouped by COD's normalized sgNumber. 226 distinct space groups appear. Companion to the COD composition-flip dataset (019fe3d8-6612-7381-bc5b-2e66e05b836d); no-C totals agree with server-side element-filter counts to <1%. Use cases: symmetry-mix trends, high-throughput fingerprint detection, crystallographic era analysis.
Where did the structures go?
Capstone of the COD series. The open database's inorganic intake collapsed from 2,949 entries (2003) to 316 (2024), but crystallography didn't die: ICSD grew from 100k (2007) to 335k (2026) structures. Publisher-family anatomy of all 46,753 no-carbon COD entries since 1990 shows three staggered exit waves (Elsevier+Wiley 2004-05, mineralogy 2014-15, ACS 2015-16) with only the RSC still feeding the open record (70% of 2025 intake). Open capture fell from ~15% to ~2% of ICSD's annual intake.
The triclinic surge has three fathers
The COD's triclinic share tripled after 2023, but each year of the surge has a different cause: 2024 is genuine experimental P-1 chemistry made visible by the lowest no-carbon intake since 1961, 2025 is a generative-model batch in disguise, and 2026 is DFT working files deposited as personal communications. None of them are marked as what they are.