THE CRYSTAL STRUCTURE OF BERGENITE, A NEW GEOMETRICAL ISOMER OF THE PHOSPHURANYLITE GROUP
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
The crystal structure of bergenite, ideally Ca2Ba4[(UO2)3O2(PO4)2]3(H2O)16, monoclinic, space group P21/c, a 10.092(1), b 17.245(2), c 17.355(2) Å, 113.678(2)°, V 2766.2(3) Å3, Z = 2, Dcalc 4.82 g/cm3, was solved by direct methods and refined by full-matrix least-squares techniques on the basis of F2 to agreement indices R1 of 5.0 % calculated for 4118 unique observed reflections (|Fo | ≥ 4F), and wR2 of 11.9 % for all data. Intensity data were collected at room temperature using MoK radiation and a CCD-based area detector. The structure of bergenite contains five symmetrically independent uranium atoms, each of which is part of a (UO2)2+ uranyl ion. The uranyl ions of U(1), U(2) and U(3) are coordinated by five additional ligands giving pentagonal bipyramids, and the uranyl ions of U(4) and U(5) are coordinated by six additional ligands yielding hexagonal bipyramids. The uranyl pentagonal bipyramids share edges, forming dimers, which are linked to uranyl hexagonal bipyramids on either side, resulting in chains of bipyramids. Each uranyl hexagonal bipyramid shares two equatorial edges with phosphate tetrahedra, and the resulting uranyl phosphate chains are linked into sheets by the sharing of vertices of phosphate tetrahedra with uranyl pentagonal bipyramids of adjacent chains. The uranyl phosphate sheet in bergenite is a new geometrical isomer of the phosphuranylite group; the phosphate tetrahedra between the uranyl chains vary orientations in an up-up-down up-up-down (uuduud) pattern, and the pairs of tetrahedra attached to uranyl hexagonal bipyramids change orientations in a complementary same-same-opposite (SSO) manner (symbol uuduudSSO). In bergenite, the uranyl phosphate sheets are oriented parallel to (¯102),
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it