naphthalene+CHO+OCH3 C12H10O2
B_5a1b7a4384 · SMILES COc1cccc2ccc(C=O)cc12 · InChIKey XSYDCPIHIFFZRU-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
46 infrared-active bands (500–3500 cm⁻¹); the strongest at 1797 cm⁻¹ (5.6 µm), 253 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)
66 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 | 71.2 | 3.24 | 91.9 | +20.7 |
| 2 | 89.0 | 3.35 | 122.5 | +33.5 |
| 3 | 134.9 | 3.39 | 144.8 | +9.8 |
| 4 | 151.0 | 6.60 | 183.6 | +32.6 |
| 5 | 183.8 | 0.79 | 195.8 | +12.0 |
| 6 | 215.4 | 1.18 | 239.3 | +23.9 |
| 7 | 236.3 | 3.82 | 248.6 | +12.3 |
| 8 | 267.0 | 0.01 | 292.8 | +25.9 |
| 9 | 324.3 | 0.32 | 336.2 | +11.9 |
| 10 | 331.9 | 0.62 | 338.4 | +6.5 |
| 11 | 407.3 | 1.27 | 411.8 | +4.5 |
| 12 | 439.1 | 3.71 | 447.8 | +8.7 |
| 13 | 467.9 | 13.30 | 473.6 | +5.6 |
| 14 | 506.7 | 1.87 | 517.6 | +10.9 |
| 15 | 518.5 | 1.79 | 522.1 | +3.6 |
| 16 | 582.6 | 3.94 | 593.6 | +11.0 |
| 17 | 594.4 | 13.19 | 600.4 | +6.1 |
| 18 | 628.5 | 4.87 | 633.4 | +4.9 |
| 19 | 669.4 | 0.01 | 683.4 | +14.0 |
| 20 | 735.5 | 12.34 | 742.7 | +7.2 |
| 21 | 751.0 | 32.03 | 757.6 | +6.6 |
| 22 | 761.3 | 16.70 | 767.5 | +6.2 |
| 23 | 799.9 | 0.51 | 813.4 | +13.5 |
| 24 | 843.4 | 58.05 | 856.0 | +12.6 |
| 25 | 874.7 | 3.18 | 882.9 | +8.1 |
| 26 | 877.4 | 2.46 | 892.9 | +15.5 |
| 27 | 952.3 | 5.38 | 966.8 | +14.5 |
| 28 | 955.3 | 32.16 | 967.7 | +12.4 |
| 29 | 965.3 | 0.27 | 993.0 | +27.8 |
| 30 | 975.3 | 1.32 | 1005.8 | +30.6 |
| 31 | 1028.7 | 10.45 | 1040.3 | +11.7 |
| 32 | 1034.0 | 0.24 | 1060.2 | +26.2 |
| 33 | 1103.3 | 18.69 | 1108.3 | +5.0 |
| 34 | 1132.1 | 54.54 | 1145.6 | +13.5 |
| 35 | 1181.7 | 8.78 | 1172.4 | -9.4 |
| 36 | 1184.7 | 1.14 | 1194.0 | +9.3 |
| 37 | 1189.1 | 91.51 | 1196.2 | +7.1 |
| 38 | 1215.0 | 37.49 | 1223.6 | +8.6 |
| 39 | 1237.9 | 60.66 | 1242.8 | +5.0 |
| 40 | 1253.4 | 0.94 | 1249.0 | -4.4 |
| 41 | 1281.8 | 22.79 | 1285.2 | +3.4 |
| 42 | 1313.5 | 148.16 | 1321.5 | +7.9 |
| 43 | 1373.3 | 22.73 | 1375.6 | +2.3 |
| 44 | 1418.0 | 61.30 | 1417.8 | -0.2 |
| 45 | 1424.1 | 63.39 | 1425.8 | +1.7 |
| 46 | 1448.0 | 13.86 | 1460.4 | +12.4 |
| 47 | 1484.8 | 33.11 | 1496.9 | +12.1 |
| 48 | 1497.4 | 18.61 | 1509.9 | +12.5 |
| 49 | 1515.6 | 44.20 | 1532.2 | +16.7 |
| 50 | 1520.4 | 6.42 | 1532.8 | +12.4 |
| 51 | 1534.4 | 15.18 | 1544.8 | +10.4 |
| 52 | 1564.2 | 7.71 | 1591.6 | +27.4 |
| 53 | 1622.4 | 89.04 | 1653.4 | +31.0 |
| 54 | 1654.4 | 15.16 | 1683.1 | +28.8 |
| 55 | 1675.6 | 123.78 | 1722.7 | +47.2 |
| 56 | 1796.9 | 252.50 | 1830.0 | +33.1 |
| 57 | 2899.7 | 184.29 | 2950.5 | +50.8 |
| 58 | 3031.9 | 58.17 | 3067.7 | +35.8 |
| 59 | 3093.5 | 38.36 | 3141.3 | +47.8 |
| 60 | 3165.4 | 18.17 | 3208.2 | +42.8 |
| 61 | 3176.5 | 5.51 | 3219.9 | +43.5 |
| 62 | 3186.8 | 1.31 | 3229.9 | +43.1 |
| 63 | 3195.2 | 19.59 | 3238.6 | +43.4 |
| 64 | 3204.0 | 31.27 | 3246.8 | +42.8 |
| 65 | 3231.9 | 12.43 | 3275.7 | +43.8 |
| 66 | 3239.8 | 0.55 | 3283.8 | +44.1 |
Second route
Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 1 cm⁻¹; wb97x max |Δω| 16 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, 2026-09-30 00:05:07 → 2026-09-30 01:10:31, 3923 s, peak 4.84 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