Update README.md

README.md

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 ---
 license: mit
+task_categories:
+  - tabular-regression
+tags:
+  - chemistry
+  - quantum-chemistry
+  - computational-chemistry
+  - density-functional-theory
+  - molecular-geometry
+  - molecular-machine-learning
+  - interatomic-potentials
+  - pyscf
+pretty_name: Chembricks ωB97M-V Organic
+size_categories:
+  - 100K<n<1M
 ---
+
+# Chembricks ωB97M-V Organic
+
+Chembricks ωB97M-V Organic is a curated computational quantum-chemistry dataset containing **801,781 molecular structures**. Each structure provides a gas-phase ωB97M-V single-point energy, HOMO and LUMO energies, an atom-resolved nuclear gradient, formal charge and spin, Cartesian coordinates, and traceable source provenance.
+
+The DFT labels were evaluated on converged gas-phase GFN2-xTB geometries. They are protocol-defined computational reference values—not experimental measurements and not universal ground truth.
+
+## Dataset summary
+
+| Property | Value |
+|---|---:|
+| Retained molecular identities | 801,781 |
+| Retained conformers | 801,781 |
+| Raw source records curated | 805,046 |
+| Duplicate source occurrences merged | 1,615 |
+| Hard-invalid source records rejected | 1,650 |
+| Quarantined source occurrences | 0 |
+| Retained records with an explicit connectivity flag | 2,791 |
+| Formal charge −1 / 0 / +1 | 3,669 / 790,722 / 7,390 |
+| PySCF spin `2S = 0` | 801,781 |
+| Electronic-structure driver | RKS for every retained structure |
+| Elements | H, B, C, N, O, F, Si, P, S, Cl, Br, I |
+| Phase | Gas |
+
+The serialized format supports multiple conformers per molecular identity. In this release, the number of retained conformers equals the number of canonical identities, so each `vacuum_conformers` array contains one retained representative.
+
+## Intended uses
+
+This dataset is suitable for research on:
+
+- molecular energy and orbital-energy regression;
+- atomistic energy/gradient and force-model development;
+- representation learning on molecular geometries;
+- uncertainty estimation and out-of-distribution detection;
+- quantum-chemistry surrogate models; and
+- analysis of SCF behavior across organic and main-group chemical space.
+
+It is not intended to provide experimental observables, solvent-phase properties, reaction barriers, DFT-optimized stationary points, or thermochemical quantities.
+
+## Release scope
+
+The release scope was fixed by a deterministic source-chunk rule:
+
+| Source campaign | Included chunk IDs | Source files | Raw records |
+|---|---:|---:|---:|
+| Campaign 1 | 0–38 | 39 | 397,482 |
+| Campaign 2 | 0–81 | 82 | 407,564 |
+| **Total** |  | **121** | **805,046** |
+
+The chunk-prefix selection is reproducible, but it was not a randomized or distribution-preserving sample. Keep the supplied source references when constructing evaluations, and do not assume that records are independently and identically distributed solely because canonical identities are unique.
+
+## From SMILES to the stored DFT result
+
+```text
+SMILES + formal charge
+        │
+        ▼
+10 candidate 3D structures generated with g-xTB
+        │
+        ▼
+gas-phase GFN2-xTB very-tight geometry optimization
+        │
+        ▼
+identity, composition, convergence and geometry validation
+        │
+        ▼
+gas-phase PySCF ωB97M-V single-point calculation
+        │
+        ▼
+energy + HOMO/LUMO + nuclear gradient + xTB geometry
+        │
+        ▼
+deduplication, conflict checks and robust outlier curation
+```
+
+The workflow starts from a molecular SMILES and explicit formal charge. g-xTB generates ten candidate three-dimensional structures. A selected candidate is optimized in the gas phase with GFN2-xTB using the very-tight convergence setting. PySCF then evaluates one ωB97M-V single point on that xTB geometry.
+
+The DFT stage does **not** optimize the geometry (`perform_opt: false`) and does not request thermochemistry (`thermo: false`). The dataset therefore contains no DFT stationary geometries, Hessians, harmonic frequencies, zero-point energies, enthalpies, or finite-temperature Gibbs free energies. A nonzero stored gradient is expected because it is evaluated at an xTB-optimized rather than ωB97M-V-optimized geometry.
+
+## Quantum-chemistry protocol
+
+| Setting | Value |
+|---|---|
+| Functional | ωB97M-V (`wb97m-v`) |
+| Functional class | Range-separated hybrid meta-GGA with VV10 nonlocal correlation |
+| Program | PySCF 2.9.0 |
+| Phase | Gas; `solvent: null` |
+| Geometry | Gas-phase GFN2-xTB very-tight optimization |
+| DFT calculation | Single point only |
+| Numerical grid | PySCF grid level 5 plus the VV10 nonlocal grid |
+| Density fitting | RI-JK through PySCF `density_fit()` |
+| Orbital basis/ECP scheme | `qmcbasis`: NWChem-format, commit-declared aug-cc-pVTZ orbital-basis and matching ccECP map for observed elements |
+| Auxiliary basis | `cc-pvdz-jkfit`; iodine override `def2-universal-jkfit` |
+| SCF level shift | 0.5 Hartree |
+| Maximum SCF cycles | 250 |
+| Driver and spin | RKS; every retained entry has PySCF `spin = Nα − Nβ = 2S = 0` |
+| Direct SCF | PySCF default behavior; no explicit screening tolerance was serialized |
+| Coordinates | Å |
+| Energies | Hartree (`Eh`) |
+| Nuclear gradient | Hartree/bohr (`Eh/a₀`) |
+
+ωB97M-V includes exact Hartree–Fock exchange. RI-JK therefore fits both the Coulomb (J) and exchange (K) contributions rather than using a Coulomb-only J-fit.
+
+CDS means **cavitation–dispersion–solvent-structure** correction. Because these calculations are gas phase and do not use SMD, `solvent_energy` and `cds_correction` are exactly zero for every retained structure.
+
+## Curation and quality control
+
+The curation procedure canonicalized identity with RDKit and applied the following non-negotiable checks:
+
+- converged GFN2-xTB geometry optimization and converged DFT SCF;
+- finite SCF, solvent, CDS, HOMO, LUMO, coordinate, and gradient values;
+- matching element composition, formal charge, electron-count parity, spin, and RKS driver;
+- one coordinate and one gradient vector per atom, with three finite Cartesian components;
+- `HOMO <= LUMO` and an SCF-cycle count between 1 and 250;
+- the expected gas-phase ωB97M-V method, basis scheme, grid, level shift, and calculation mode;
+- no severe atomic collisions; and
+- robust median/MAD energy screens within canonical-identity and molecular-formula groups.
+
+Within one canonical identity, symmetry-aware exact duplicates were identified after atom mapping and rigid alignment. Both the heavy-atom and all-atom RMSD had to be at most `10^-6 Å`. Duplicate labels were required to agree within `10^-5 Hartree` for SCF energy, solvent energy, CDS correction, HOMO, and LUMO; aligned gradient components were required to agree within `10^-6 Hartree/bohr`. One deterministic representative was retained and redundant occurrences were attached to its provenance rather than emitted as extra training examples.
+
+The released curation policy allows a composition-consistent geometry to differ in connectivity from its canonical SMILES. The diagnostic proximity graph uses `1.25 ×` the sum of RDKit covalent radii when checking expected SMILES bonds. The **2,791 retained structures** for which an expected bond was not present carry:
+
+```json
+"curation_flags": ["connectivity_mismatch_allowed_by_mild"]
+```
+
+These structures are intentionally visible rather than silently relabeled. Users can retain them, exclude them, or evaluate them as a separate slice. Geometry-derived identity inference was permitted when source SMILES was absent and uniquely resolvable, but no retained record in this release required it.
+
+### Curation accounting
+
+| Outcome | Count | Share of 805,046 raw records |
+|---|---:|---:|
+| Retained distinct representative | 801,781 | 99.594% |
+| Duplicate occurrence merged into provenance | 1,615 | 0.201% |
+| Quarantined | 0 | 0.000% |
+| Hard rejected | 1,650 | 0.205% |
+| **Total** | **805,046** | **100.000%** |
+
+The final artifact passed streaming standard-JSON parsing, non-finite-value checks, ID uniqueness checks, exact accounting closure, source-reference validation, geometry/gradient shape checks, method-profile validation, and a complete SHA-256 rehash.
+
+## Distributed file
+
+| File | Size | SHA-256 |
+|---|---:|---|
+| `wb97m_v_organic_argonne_public_2026-08-16.json` | 3,266,960,267 bytes | `e1abc9a68ca2a782d9bf0c9605325a9be67607c68e394f7b365df529599cffeb` |
+
+The artifact is standard JSON, not JSON Lines. It uses an identity-grouped envelope rather than storing one independent object per line:
+
+```text
+root
+├── schema_version
+├── metadata
+├── source_files[]
+└── molecules[]
+    ├── molecular identity
+    └── vacuum_conformers[]
+        ├── geometry
+        ├── log_data
+        └── provenance and curation fields
+```
+
+## JSON field reference
+
+### Top-level fields
+
+| Field | Type | Meaning |
+|---|---|---|
+| `schema_version` | string | Serialization schema version; currently `1.0.0`. |
+| `metadata` | object | Dataset identity, version, counts, curation settings, units, calculation protocol, and manifest fingerprints. |
+| `source_files` | array of objects | Table of source-file provenance. `source_ref.file_id` values resolve against this table. |
+| `molecules` | array of objects | The 801,781 retained canonical molecular identities. |
+
+### `metadata`
+
+| Field | Meaning |
+|---|---|
+| `dataset_name` | Human-readable dataset name. |
+| `dataset_version` | Version of the curated release. |
+| `description` | Short description of the retained labels and structures. |
+| `counts` | Exact `molecules`, `conformers`, and `source_records` counts. |
+| `state_mapping` | Declares that `vacuum_conformers` stores validated gas-phase DFT states. |
+| `identity_policy` | Canonical molecular-identity rule. |
+| `curation_policy` | Duplicate, label-tolerance, identity-inference, and connectivity-policy settings. |
+| `units` | Canonical units for coordinates, energies, gradients, and timing data. |
+| `calculation_protocols` | Full protocol object referenced by each conformer's `protocol_id`. |
+| `source_manifest_logical_sha256` | Logical fingerprint of the source manifest used for the build. |
+| `dependency_manifest_logical_sha256` | Logical fingerprint of the curation implementation and runtime dependencies. |
+| `curation_config_logical_sha256` | Logical fingerprint of the effective curation configuration. |
+
+### `source_files[]`
+
+| Field | Type | Meaning |
+|---|---|---|
+| `id` | integer | Dataset-local file identifier used by conformer provenance. |
+| `relative_path` | string | Stable logical source path; it is not a local machine path. |
+| `collection` | string | Source campaign identifier. |
+| `protocol_id` | string | Calculation protocol applied to records in the source file. |
+| `record_count` | integer | Number of raw records in that source file. |
+| `size_bytes` | integer | Raw source-file size in bytes. |
+| `sha256` | string | SHA-256 digest of the raw source file. |
+
+### `molecules[]`
+
+| Field | Type | Meaning |
+|---|---|---|
+| `molecule_id` | string | Deterministic ID of the form `mol-` plus 24 hexadecimal characters, derived from the canonical SMILES with a versioned SHA-256 namespace. It is a dataset ID, not an InChIKey. |
+| `canonical_smiles` | string | RDKit canonical isomeric SMILES used as the molecular identity. |
+| `original_smiles` | array of strings | Unique original SMILES carried by retained representative records grouped under this identity. |
+| `formal_charge` | integer | Molecular formal charge; validated against both identity and `log_data.charge`. |
+| `vacuum_conformers` | array of objects | Retained gas-phase conformer records. The schema supports multiple conformers; this release contains one per identity. |
+
+### `vacuum_conformers[]`
+
+| Field | Type | Meaning |
+|---|---|---|
+| `conformer_id` | string | Deterministic ID of the form `conf-` plus 24 hexadecimal characters, derived from canonical identity and the normalized conformer payload. |
+| `geometry` | object | Ordered atom symbols and Cartesian coordinates of the converged xTB geometry. |
+| `log_data` | object | Normalized DFT labels, protocol fields, gradient, and optional runtime diagnostics. |
+| `source_occurrence_count` | integer | Number of raw occurrences represented by this retained conformer. A value greater than one means redundant occurrences were merged. |
+| `source_ref` | object | Provenance of the deterministic representative. |
+| `merged_source_refs` | array of objects, optional | Provenance of redundant source occurrences merged into the representative. These are not extra training examples. |
+| `curation_flags` | array of strings, optional | Explicit retained-policy flags. Absence means that no such flag applies. |
+
+### `geometry`
+
+| Field | Type | Meaning |
+|---|---|---|
+| `elements` | array of strings, length `N` | Atomic symbols in the stored geometry atom order. |
+| `coordinates` | array of `[x, y, z]`, shape `[N, 3]` | Finite Cartesian coordinates aligned row-for-row with `elements`; unit is Å. |
+| `unit` | string | Always `angstrom`. |
+| `method` | string | `xTB`, indicating that the geometry came from the GFN2-xTB optimization. |
+
+`geometry.elements[i]`, `geometry.coordinates[i]`, and `log_data.gradient[i]` always refer to the same atom.
+
+### `log_data`
+
+| Field | Type | Unit | Meaning |
+|---|---|---|---|
+| `converged` | boolean | — | Always `true` for retained SCF calculations. |
+| `scf_energy` | number | Hartree | Total gas-phase ωB97M-V SCF energy. |
+| `homo` | number | Hartree | Highest occupied molecular-orbital energy. |
+| `lumo` | number | Hartree | Lowest unoccupied molecular-orbital energy. |
+| `gradient` | array of `[gx, gy, gz]`, shape `[N, 3]` | Hartree/bohr | Nuclear derivative `∂E/∂R` in geometry atom order. A force target is the negative gradient. |
+| `charge` | integer | elementary charge | Total molecular charge; equals the enclosing `formal_charge`. |
+| `spin` | integer | — | PySCF spin `Nα − Nβ = 2S`; every retained value is `0`. This is not the multiplicity `2S + 1`. |
+| `driver` | string | — | SCF driver; always `RKS` in this release. |
+| `cycles` | integer | — | Number of SCF cycles, from 1 through 250. |
+| `xc` | string | — | Exchange-correlation functional identifier; `wb97m-v`. |
+| `basis` | string | — | Basis/ECP scheme identifier; `qmcbasis`. Resolve details through the matching protocol object. |
+| `grid_level` | integer | — | PySCF numerical grid level; `5`. |
+| `level_shift` | number | Hartree | SCF level shift; `0.5`. |
+| `solvent` | null | — | Always `null`; calculations are gas phase. |
+| `solvent_energy` | number | Hartree | Always `0.0` in this gas-phase release. |
+| `cds_correction` | number | Hartree | Always `0.0`; CDS is the cavitation–dispersion–solvent-structure correction. |
+| `perform_opt` | boolean | — | Always `false`; no DFT geometry optimization was performed. |
+| `thermo` | boolean | — | Always `false`; no Hessian/frequency thermochemistry was requested. |
+| `protocol_id` | string | — | Foreign key into `metadata.calculation_protocols`; here `argonne_dev_crux_0153337`. |
+| `time` | number, optional | seconds | Reported total calculation timing diagnostic. |
+| `pyscf_time` | number, optional | seconds | Reported PySCF-stage timing diagnostic. |
+| `memory_usage_mb` | number, optional | MB | Reported memory-use diagnostic. |
+| `ncores` | integer, optional | cores | Reported CPU-core count. |
+
+Runtime and resource fields are environment-dependent diagnostics, not molecular labels.
+
+### Provenance objects
+
+`source_ref` and entries in optional `merged_source_refs` contain:
+
+| Field | Meaning |
+|---|---|
+| `file_id` | Foreign key into top-level `source_files`. |
+| `result_index` | Zero-based record index inside that source file. |
+| `uuid` | Original source UUID when supplied. |
+| `relative_path` | Stable logical source path. |
+| `collection` | Source campaign identifier. |
+
+For every conformer, `source_occurrence_count` is the representative occurrence plus the number of entries in `merged_source_refs`.
+
+## Memory-safe loading
+
+The JSON file is approximately 3.27 GB, so avoid `json.load()` unless sufficient memory is available. The top-level `molecules` array can be streamed with [`ijson`](https://pypi.org/project/ijson/):
+
+```bash
+pip install huggingface_hub ijson
+```
+
+```python
+from huggingface_hub import hf_hub_download
+import ijson
+
+path = hf_hub_download(
+    repo_id="chembricks/WB96MV-ORGANIC",
+    filename="wb97m_v_organic_argonne_public_2026-08-16.json",
+    repo_type="dataset",
+)
+
+with open(path, "rb") as handle:
+    molecules = ijson.items(handle, "molecules.item")
+    for molecule in molecules:
+        conformer = molecule["vacuum_conformers"][0]
+        elements = conformer["geometry"]["elements"]
+        coordinates_angstrom = conformer["geometry"]["coordinates"]
+        energy_hartree = conformer["log_data"]["scf_energy"]
+        gradient_hartree_per_bohr = conformer["log_data"]["gradient"]
+        # Train, transform, or yield the record here.
+```
+
+## Recommended ML practice
+
+- Split on `molecule_id`, canonical SMILES, or a molecular scaffold—not on provenance occurrences.
+- Do not expand `merged_source_refs` into repeated examples; those objects document redundancy.
+- Keep the coordinate, element, and gradient arrays in exactly the same atom order.
+- If training forces, use `force = -gradient` and convert both energy and length units consistently.
+- Preserve `protocol_id`, even though the release currently contains one protocol.
+- Decide explicitly how to handle the 2,791 `connectivity_mismatch_allowed_by_mild` structures and report that decision.
+- Do not compare raw total energies across different elemental compositions as though they were directly normalized molecular properties.
+- Prefer scaffold-aware or source-aware evaluation when estimating chemical generalization.
+
+## Limitations
+
+- These are computed labels and inherit the approximations of GFN2-xTB geometries, ωB97M-V, the basis/ECP scheme, RI-JK density fitting, and the numerical settings.
+- The structures are not DFT stationary points; gradients generally do not vanish.
+- The release contains closed-shell RKS calculations only and does not represent open-shell chemistry.
+- It contains gas-phase values only. Solvation, condensed-phase effects, and finite-temperature thermochemistry are absent.
+- Canonical SMILES is the identity key, but 2,791 retained geometries carry an explicit connectivity-change flag.
+- The deterministic source-chunk selection is not equivalent to a random sample of chemical space.
+- Timing and memory fields depend on the calculation environment and should not be treated as intrinsic molecular properties.
+
+## License
+
+The dataset is released under the MIT License.
+
+## Citation
+
+If you use the dataset, cite the Hugging Face repository and the ωB97M-V method paper:
+
+```bibtex
+@misc{chembricks_wb97mv_organic_2026,
+  author       = {Chembricks},
+  title        = {Chembricks ωB97M-V Organic},
+  year         = {2026},
+  howpublished = {Hugging Face dataset},
+  url          = {https://huggingface.co/datasets/chembricks/WB96MV-ORGANIC},
+  note         = {Version 2026-08-16-v1-mild}
+}
+```
+
+- N. Mardirossian and M. Head-Gordon, “ωB97M-V: A combinatorially optimized, range-separated hybrid, meta-GGA density functional with VV10 nonlocal correlation,” *Journal of Chemical Physics* **144**, 214110 (2016). [DOI: 10.1063/1.4952647](https://doi.org/10.1063/1.4952647)
+- [PySCF density-fitting documentation](https://pyscf.org/user/df.html)