naphthalene+CH3+OCH3 C12H12O
B_246b2a4557 · SMILES COc1c(C)ccc2ccccc12 · InChIKey GXIFCLBPAVRDAL-UHFFFAOYSA-N
finite-difference Hessian noisy
finite-difference Hessian noisy (analytic check differs > 15 cm⁻¹). The finite-difference Hessian and the analytic Hessian of the same geometry differ by more than 15 cm⁻¹ on at least one frequency; the numerical route is the noisy one.Infrared spectrum at the cheap level (B3LYP/6-31G*, the pipeline's input)
How to read this
52 infrared-active bands (500–3500 cm⁻¹); the strongest at 1122 cm⁻¹ (8.9 µm), 79 km/mol.
cheap input (B3LYP): blue curve, sticks orange at the curve's peak scale. Lorentzian, FWHM 10 cm⁻¹; axis in km mol⁻¹ per cm⁻¹.
Band heights from the molecule's dipole derivatives and the same B3LYP Hessian as the listed positions (double harmonic).
Predicted spectrum (rung 3, the learned correction): computed by the pipeline, not drawn on this page; licensed for ring-ip, CH-stretch, CH-oop (decision 65).
How well is this shape known?
| measured on (ΔH network v1.3) | spectrum overlap cheap → corrected | height error cheap → corrected |
|---|---|---|
| 8 unseen simple aromatics (layer A), DFT stand-in for the higher level | 0.28 → 0.98 | 0.23 → 0.10 |
| 31 molecules of unseen scaffolds, DFT stand-in for the higher level | 0.37 → 0.97 | 0.51 → 0.24 |
| against coupled cluster | not measured for this version | |
Overlap: similarity of the two broadened spectra (1 = the same shape). Height error: relative error per band, weighted by height (0 = the same heights). "Corrected" is the learned correction on molecules it never saw; the pipeline serves it for the licensed families. Open: the dipole derivatives themselves are computed at the cheap level (on benzene they differ from coupled cluster by about 20 %).
Harmonic frequencies at the cheap level (deck v1: B3LYP and ωB97X, 6-31G*, at the B3LYP geometry)
69 vibrational modes; imaginary modes negative. Shift = ωB97X − B3LYP; height = B3LYP band height (km/mol).
The B3LYP bands are drawn in the spectrum above; the table adds their heights, the ωB97X positions and the shift.
| # | B3LYP (cm⁻¹) | height (km/mol) | ωB97X (cm⁻¹) | shift |
|---|---|---|---|---|
| 1 | 75.7 | 2.60 | 46.0 | -29.7 |
| 2 | 98.5 | 0.53 | 84.2 | -14.3 |
| 3 | 109.8 | 0.13 | 115.1 | +5.2 |
| 4 | 132.8 | 1.30 | 139.4 | +6.6 |
| 5 | 164.8 | 0.20 | 148.4 | -16.5 |
| 6 | 195.6 | 1.40 | 203.8 | +8.3 |
| 7 | 260.1 | 0.19 | 266.2 | +6.1 |
| 8 | 266.4 | 3.13 | 275.0 | +8.6 |
| 9 | 318.9 | 7.41 | 327.3 | +8.4 |
| 10 | 360.6 | 2.53 | 370.3 | +9.7 |
| 11 | 437.9 | 0.90 | 442.1 | +4.3 |
| 12 | 444.8 | 3.83 | 454.1 | +9.2 |
| 13 | 487.4 | 0.68 | 492.8 | +5.3 |
| 14 | 512.4 | 0.27 | 522.2 | +9.8 |
| 15 | 527.9 | 0.36 | 533.4 | +5.5 |
| 16 | 580.8 | 1.50 | 587.8 | +7.0 |
| 17 | 604.8 | 2.86 | 616.2 | +11.3 |
| 18 | 686.5 | 3.25 | 696.2 | +9.7 |
| 19 | 705.9 | 6.30 | 718.6 | +12.6 |
| 20 | 737.5 | 5.93 | 743.3 | +5.8 |
| 21 | 762.0 | 13.46 | 771.2 | +9.2 |
| 22 | 801.5 | 6.43 | 818.5 | +17.0 |
| 23 | 828.3 | 40.96 | 843.1 | +14.8 |
| 24 | 871.1 | 1.56 | 879.3 | +8.2 |
| 25 | 886.6 | 1.53 | 903.9 | +17.3 |
| 26 | 936.7 | 5.09 | 946.7 | +10.1 |
| 27 | 953.8 | 0.20 | 985.3 | +31.6 |
| 28 | 964.5 | 1.46 | 996.9 | +32.4 |
| 29 | 992.2 | 0.03 | 1019.2 | +27.1 |
| 30 | 1012.6 | 17.07 | 1023.0 | +10.4 |
| 31 | 1045.6 | 24.98 | 1057.7 | +12.2 |
| 32 | 1058.1 | 8.73 | 1068.2 | +10.2 |
| 33 | 1074.7 | 3.80 | 1079.2 | +4.6 |
| 34 | 1122.2 | 78.62 | 1133.8 | +11.6 |
| 35 | 1182.0 | 6.41 | 1167.8 | -14.2 |
| 36 | 1184.8 | 1.08 | 1186.7 | +2.0 |
| 37 | 1186.4 | 1.75 | 1190.7 | +4.3 |
| 38 | 1207.9 | 8.37 | 1213.4 | +5.5 |
| 39 | 1231.0 | 17.31 | 1238.7 | +7.7 |
| 40 | 1249.6 | 3.41 | 1243.3 | -6.3 |
| 41 | 1273.3 | 55.42 | 1285.3 | +12.0 |
| 42 | 1292.4 | 16.36 | 1300.4 | +8.0 |
| 43 | 1379.5 | 24.27 | 1378.5 | -1.0 |
| 44 | 1413.5 | 29.98 | 1421.1 | +7.5 |
| 45 | 1417.5 | 26.81 | 1423.3 | +5.8 |
| 46 | 1438.7 | 5.13 | 1449.0 | +10.3 |
| 47 | 1472.3 | 0.94 | 1485.6 | +13.3 |
| 48 | 1499.7 | 0.91 | 1506.0 | +6.3 |
| 49 | 1513.8 | 2.81 | 1520.2 | +6.5 |
| 50 | 1518.2 | 5.33 | 1524.5 | +6.3 |
| 51 | 1520.3 | 6.79 | 1527.6 | +7.3 |
| 52 | 1525.1 | 2.91 | 1536.3 | +11.2 |
| 53 | 1536.7 | 8.03 | 1539.6 | +3.0 |
| 54 | 1562.1 | 10.94 | 1590.3 | +28.1 |
| 55 | 1623.9 | 14.13 | 1657.8 | +33.9 |
| 56 | 1659.5 | 9.95 | 1687.0 | +27.6 |
| 57 | 1682.8 | 0.47 | 1729.2 | +46.4 |
| 58 | 3028.2 | 46.44 | 3063.4 | +35.2 |
| 59 | 3038.1 | 42.01 | 3075.8 | +37.7 |
| 60 | 3087.8 | 40.48 | 3135.7 | +47.9 |
| 61 | 3096.2 | 19.89 | 3144.8 | +48.6 |
| 62 | 3145.2 | 41.41 | 3189.4 | +44.3 |
| 63 | 3146.4 | 1.35 | 3193.6 | +47.2 |
| 64 | 3174.1 | 6.76 | 3218.2 | +44.2 |
| 65 | 3177.3 | 1.70 | 3220.8 | +43.5 |
| 66 | 3188.4 | 10.37 | 3231.7 | +43.3 |
| 67 | 3193.3 | 36.54 | 3237.0 | +43.7 |
| 68 | 3203.9 | 32.92 | 3246.9 | +43.1 |
| 69 | 3223.5 | 11.49 | 3267.3 | +43.8 |
Second route
Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 1 cm⁻¹; wb97x max |Δω| 49 cm⁻¹.
Provenance
- Releases: none yet
- Entered the corpus as: cores with one or two substituents, enumerated from the parents (layer B)
- Run: ubuntu-32gb-hel1-18, 2026-09-28 21:43:19 → 2026-09-28 22:45:20, 3721 s, peak 4.81 GB, deck 9e27bf8e9348
- Imaginary modes: B3LYP 0, ωB97X 0
- Cheap-level band heights: dipole derivatives dipole_b3lyp_cphf.npz, Hessian hessian_b3lyp.npz
- Source files: corpus factory · manifest