PROVENANCE - Caffeine (CAS 58-08-2) - ready-to-print release 2026-10-28, package r19
=====================================================================
WHERE THE ATOM POSITIONS COME FROM
  Source record : PubChem Compound CID 2519 (C8H10N4O2), 3D conformer
                  https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/2519/record/SDF?record_type=3d
  Conformer ID  : 000009D700000001 (PUBCHEM_CONFORMER_ID)
  Nature        : COMPUTED. The 3D conformer was computed by PubChem
                  (PubChem3D, using OMEGA). It is one calculated conformer,
                  not an experimentally determined structure.
  Atoms, bonds  : 24 atoms, 25 bonds; all 10 hydrogen atoms are included.
  Coordinates   : first retrieved from PubChem on 2026-10-08 (the "Retrieved"
                  date on the licence page); geometry taken into our record on
                  2026-10-17; compared at build time with a fresh copy downloaded
                  from PubChem on 2026-10-24
                  (source/ below): largest difference of any atom
                  position 0.0000 A.
  Source file   : source/pubchem_CID2519_3d.sdf
  Fingerprint   : SHA-256 of the atom and bond block of that file
                  c977e2fe9bafcab1dabe45f5537a1a998908552bf1a412343a101d5f1e962eb4
                  The checksum of the whole file changes on every download
                  (PubChem writes a timestamp into line 2), so this block is
                  the stable identity of the coordinates.

WHAT WE CHANGED FOR PRINTING
  - The model is built from these coordinates at scale 1 A = 10.60 mm.
    Gate G_geometria_molekuly on this STL: PASS (every source point
    within 0.001 mm of the printed surface outside the pencil and cup
    zones; GATES_REPORT.txt).
  - Sphere and bond diameters are stylised for printing; they do not show
    van der Waals radii or electron density.
  - Added as separate solids joined to the molecule: the display base and
    11 vertical pencils with 45-degree cups (PRINT_METHODOLOGY.txt).

LICENCE
  Model: CC BY-NC-SA 4.0, see LICENSE.txt (section 5 covers the source data).
