naphthalene+CH3+NO2 C11H9NO2
B_2de8fb1eb7 · SMILES Cc1cc([N+](=O)[O-])cc2ccccc12 · InChIKey ZHWLZNWJMCOUIZ-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
38 infrared-active bands (500–3500 cm⁻¹); the strongest at 1389 cm⁻¹ (7.2 µm), 278 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)
63 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 | 57.0 | 0.05 | 108.7 | +51.7 |
| 2 | 93.3 | 0.72 | 125.3 | +32.0 |
| 3 | 147.0 | 0.18 | 157.8 | +10.9 |
| 4 | 180.1 | 0.02 | 203.5 | +23.4 |
| 5 | 187.7 | 1.16 | 213.7 | +26.0 |
| 6 | 216.7 | 1.26 | 249.1 | +32.4 |
| 7 | 277.0 | 0.60 | 286.0 | +9.0 |
| 8 | 286.7 | 4.15 | 299.7 | +13.0 |
| 9 | 343.1 | 0.43 | 348.3 | +5.3 |
| 10 | 411.2 | 0.13 | 423.1 | +11.9 |
| 11 | 432.2 | 3.79 | 442.8 | +10.6 |
| 12 | 502.4 | 1.21 | 513.7 | +11.4 |
| 13 | 508.4 | 2.12 | 514.2 | +5.7 |
| 14 | 535.8 | 0.88 | 540.9 | +5.1 |
| 15 | 545.2 | 2.58 | 554.3 | +9.1 |
| 16 | 584.6 | 1.47 | 591.5 | +6.9 |
| 17 | 615.1 | 6.88 | 619.3 | +4.2 |
| 18 | 629.8 | 0.53 | 643.3 | +13.4 |
| 19 | 742.0 | 1.25 | 751.1 | +9.1 |
| 20 | 748.7 | 0.14 | 763.4 | +14.7 |
| 21 | 778.0 | 38.91 | 792.8 | +14.8 |
| 22 | 790.8 | 17.74 | 804.3 | +13.5 |
| 23 | 802.8 | 34.32 | 815.6 | +12.8 |
| 24 | 876.5 | 0.14 | 892.1 | +15.6 |
| 25 | 889.0 | 2.92 | 896.9 | +7.9 |
| 26 | 913.0 | 2.96 | 921.1 | +8.2 |
| 27 | 934.6 | 17.61 | 955.8 | +21.2 |
| 28 | 960.5 | 14.41 | 975.6 | +15.1 |
| 29 | 966.8 | 5.63 | 996.0 | +29.2 |
| 30 | 998.1 | 0.04 | 1025.9 | +27.8 |
| 31 | 1016.9 | 1.62 | 1026.9 | +10.0 |
| 32 | 1056.3 | 4.18 | 1064.3 | +8.0 |
| 33 | 1079.2 | 2.43 | 1089.8 | +10.6 |
| 34 | 1092.5 | 0.11 | 1099.7 | +7.2 |
| 35 | 1120.7 | 54.48 | 1131.9 | +11.1 |
| 36 | 1179.5 | 5.12 | 1172.8 | -6.8 |
| 37 | 1200.0 | 0.59 | 1195.8 | -4.2 |
| 38 | 1239.9 | 1.29 | 1233.1 | -6.8 |
| 39 | 1265.5 | 3.71 | 1261.9 | -3.6 |
| 40 | 1304.3 | 1.49 | 1310.4 | +6.1 |
| 41 | 1389.4 | 278.24 | 1386.0 | -3.4 |
| 42 | 1396.2 | 166.38 | 1420.5 | +24.3 |
| 43 | 1412.8 | 4.45 | 1433.3 | +20.5 |
| 44 | 1430.5 | 7.58 | 1442.6 | +12.1 |
| 45 | 1445.4 | 2.55 | 1461.2 | +15.9 |
| 46 | 1472.9 | 22.79 | 1482.6 | +9.7 |
| 47 | 1497.9 | 0.45 | 1515.6 | +17.7 |
| 48 | 1514.7 | 7.94 | 1525.4 | +10.7 |
| 49 | 1530.0 | 3.79 | 1541.5 | +11.5 |
| 50 | 1564.5 | 19.03 | 1592.0 | +27.4 |
| 51 | 1619.4 | 113.72 | 1645.7 | +26.2 |
| 52 | 1648.0 | 0.13 | 1679.7 | +31.7 |
| 53 | 1666.2 | 67.45 | 1694.4 | +28.2 |
| 54 | 1679.2 | 26.14 | 1723.8 | +44.7 |
| 55 | 3045.1 | 21.17 | 3081.3 | +36.1 |
| 56 | 3095.8 | 16.12 | 3146.6 | +50.7 |
| 57 | 3137.5 | 13.50 | 3184.3 | +46.8 |
| 58 | 3187.2 | 0.36 | 3229.7 | +42.6 |
| 59 | 3195.3 | 8.78 | 3237.9 | +42.6 |
| 60 | 3210.4 | 23.18 | 3252.8 | +42.4 |
| 61 | 3221.0 | 16.46 | 3264.4 | +43.3 |
| 62 | 3241.4 | 1.12 | 3284.6 | +43.2 |
| 63 | 3244.3 | 2.11 | 3287.6 | +43.3 |
Second route
Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 2 cm⁻¹; wb97x max |Δω| 21 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, 2026-09-29 03:04:27 → 2026-09-29 04:04:07, 3580 s, peak 4.57 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