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.

SCOPE
The 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)

PROVENANCE
All 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.

PREPRINT
An 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).

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

KEYWORDS
density 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