ESPOIR : A Program for Solving Structures by Monte Carlo from Powder Diffraction Data
Bibliographic record
Abstract
Abstract A direct-space program (ESPOIR) for the crystal structure solution of small molecules, from powder diffraction data, is developed under the GNU Public License. The program allows solving the structures of the two samples distributed during the Structure Determination by Powder Diffractometry Round Robin (SDPDRR) : the tetracycline hydrochloride and a cobalt-amine. Three calculation modes are possible, either locating up to 4 different molecule fragments, or starting from a set of randomly distributed atoms, or mixed approaches. Introduction Powder diffraction is a theatre for the development of unconventional methods for stucture solution (different from classical Patterson and direct methods). However, less than 100 structures were solved from unconventional methods, and are reported in the SDPD (Structure Determination by Powder Diffractometry) Database [1]. Trying to locate a molecule in a crystalline cell while matching to either extracted "|Fobs| " or the full powder pattern or the Patterson function
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.003 | 0.004 |
| Meta-epidemiology (narrow) | 0.002 | 0.002 |
| Meta-epidemiology (broad) | 0.002 | 0.002 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.002 | 0.002 |
| Open science | 0.005 | 0.002 |
| Research integrity | 0.002 | 0.003 |
| Insufficient payload (model declined to judge) | 0.094 | 0.019 |
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 itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".