Mode-Selective CuI Anchoring on Lignin-Inspired Fiber Interfaces: A DFT Cluster-Model Study — Computational Audit Dataset (v9.5)

Computational audit dataset accompanying the manuscript "Mode-Selective CuI Anchoring on Lignin-Inspired Fiber Interfaces: A DFT Cluster-Model Study" (Ursachi, submitted to ACS Applied Engineering Materials, 2026).

This deposit contains the complete computational pipeline supporting a DFT cluster-model investigation of copper iodide (CuI) anchoring chemistry on lignin-bearing natural fibers. Calculations are performed at the B3LYP-D3(BJ)/def2-TZVP level using ORCA 6.1.1 with RIJCOSX, def2/J auxiliary basis, TightSCF, and DefGrid3, with SMD(water) single-point corrections in the FINAL SINGLE POINT ENERGY (FSP) convention.

SCOPEThe dataset spans four copper coordination environments (naked Cu(+), CuI monomer, neutral Cu2I2 rhombic dimer, iodide-saturated [CuI2](-) anion) and lignin-inspired ligand proxies (guaiacol, phenol, anisole, catechol, methanol, water, galacturonic acid, veratrole, and substituted methoxyphenols). The principal scientific result is that copper anchoring on lignin-rich fibers is a state-dependent, mode-selective property of the (Cu coordination state, ligand functional group, accessible binding mode) tuple rather than a single per-site phenolic-O versus methanol-O affinity ranking.

CONTENTS- audit_final/: ORCA inputs, outputs, derived analysis tables, vibrational frequency   audits, classifier results, and the canonical BINDING_SURVIVAL_TABLE.csv (39 rows   mapping each Cu environment + ligand combination to its final geometry, binding   energies in gas and SMD water, key Cu-donor distances, vibrational analysis, and   binding-class verdict)- audit_final/RAW_FILE_INDEX.csv: SHA-256 manifest covering all production .out files- audit_final/cu2i2_veratrole_pi_v2_opt_freq/: independent confirmation Opt+Freq   calculation for the central Cu2I2-veratrole eta2-arene pi structure (cycle-23   convergence; n_imag = 1 small mode at -15.82 cm-1 attributed to hindered methoxy-  rotor torsion on the flat eta2-arene pi PES; full disclosure in manuscript SI   Section S8)- audit_final/cu2i2_veratrole_pi_v2_smd_sp/: SMD-FSP single-point on v2 geometry;   yields BE_gas = -23.71 kcal/mol, BE_smd = -23.00 kcal/mol, agreeing with the v1   production result (-22.98 / -23.11) within chemical-significance threshold- figures/: Figure 1-4 source files, geometric structure files (XYZ), and rendering   scripts- reproducibility/REPRODUCE.md: instructions to reconstruct any ORCA input from the   canonical CSVs and re-execute on standard CPU compute- manuscript/: SI text drafts and provenance notes- CITATION.cff: structured citation metadata- CHANGELOG.md: version history (v8 preprint -> v9 reframing -> v9.5 ACS submission)

PROVENANCEAll raw ORCA output files are SHA-256 indexed in audit_final/RAW_FILE_INDEX.csv. The distilled scientific record (geometries, energies, frequencies, classifier verdicts) is reproducible from the canonical CSVs. Wavefunction files (.gbw) and density files are excluded from the deposit per repository policy and are regenerable by warm-start from the deposited geometries.

PREPRINTAn earlier version of this work (v8) was deposited at Research Square (DOI: 10.21203/rs.3.rs-8935698/v1). The v9 series reflects a substantial scientific revision following an internal computational reproducibility audit: the central per-site oxygen-donor selectivity claim of v8 is reversed, the manuscript is reframed around mode-selective CuI cluster anchoring with two productive Cu2I2 channels (kappa2-O,O bidentate and eta2-arene pi).

LICENSEDataset: CC-BY-4.0Code (rendering scripts, reproducibility tooling): MIT

KEYWORDSdensity functional theory, DFT, copper iodide, lignin, mode-selective anchoring, cluster model, textile coatings, B3LYP-D3(BJ), ORCA, conductive textiles, biomass-derived materials, computational chemistry, reproducibility audit