naphthalene+CH3+NO2 C11H9NO2
B_38fc2ba52a · SMILES Cc1cccc2c([N+](=O)[O-])cccc12 · InChIKey AOSRALZFDNFXFZ-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
43 infrared-active bands (500–3500 cm⁻¹); the strongest at 1377 cm⁻¹ (7.3 µm), 229 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 | 57.6 | 0.48 | 89.3 | +31.7 |
| 2 | 73.0 | 0.84 | 124.3 | +51.3 |
| 3 | 174.2 | 0.25 | 189.1 | +14.9 |
| 4 | 180.9 | 1.41 | 198.8 | +17.8 |
| 5 | 198.3 | 1.58 | 228.9 | +30.6 |
| 6 | 218.9 | 2.45 | 234.8 | +15.9 |
| 7 | 256.8 | 1.06 | 272.1 | +15.3 |
| 8 | 295.6 | 0.37 | 303.3 | +7.7 |
| 9 | 369.2 | 1.45 | 379.4 | +10.1 |
| 10 | 395.6 | 1.51 | 406.1 | +10.4 |
| 11 | 457.1 | 2.55 | 469.2 | +12.1 |
| 12 | 480.1 | 0.41 | 489.4 | +9.3 |
| 13 | 497.7 | 0.92 | 503.2 | +5.5 |
| 14 | 506.5 | 1.63 | 512.1 | +5.6 |
| 15 | 553.4 | 3.21 | 563.5 | +10.1 |
| 16 | 589.2 | 1.36 | 598.9 | +9.8 |
| 17 | 609.1 | 3.30 | 618.0 | +8.9 |
| 18 | 647.6 | 2.17 | 658.9 | +11.2 |
| 19 | 745.0 | 8.70 | 755.8 | +10.8 |
| 20 | 758.7 | 6.43 | 775.3 | +16.6 |
| 21 | 777.3 | 20.96 | 795.1 | +17.8 |
| 22 | 801.0 | 0.63 | 806.2 | +5.3 |
| 23 | 812.7 | 62.94 | 823.5 | +10.8 |
| 24 | 840.7 | 2.19 | 856.4 | +15.6 |
| 25 | 867.5 | 1.58 | 876.9 | +9.4 |
| 26 | 899.2 | 23.77 | 916.2 | +17.0 |
| 27 | 923.1 | 0.28 | 938.7 | +15.7 |
| 28 | 947.1 | 0.95 | 965.4 | +18.4 |
| 29 | 987.2 | 1.32 | 1016.4 | +29.2 |
| 30 | 993.5 | 0.47 | 1024.4 | +30.9 |
| 31 | 1023.9 | 7.96 | 1034.2 | +10.3 |
| 32 | 1078.1 | 2.11 | 1085.3 | +7.2 |
| 33 | 1103.6 | 5.77 | 1104.0 | +0.4 |
| 34 | 1115.9 | 9.08 | 1129.3 | +13.4 |
| 35 | 1136.9 | 0.34 | 1151.7 | +14.8 |
| 36 | 1199.9 | 0.56 | 1200.2 | +0.3 |
| 37 | 1211.5 | 3.92 | 1215.4 | +3.9 |
| 38 | 1228.6 | 13.72 | 1236.4 | +7.8 |
| 39 | 1256.8 | 10.38 | 1250.0 | -6.8 |
| 40 | 1285.9 | 3.81 | 1298.5 | +12.6 |
| 41 | 1376.7 | 229.06 | 1375.3 | -1.3 |
| 42 | 1390.6 | 3.54 | 1395.5 | +4.9 |
| 43 | 1398.1 | 105.79 | 1438.5 | +40.4 |
| 44 | 1440.0 | 20.63 | 1445.5 | +5.4 |
| 45 | 1445.4 | 3.60 | 1459.8 | +14.4 |
| 46 | 1460.3 | 2.21 | 1471.4 | +11.1 |
| 47 | 1506.7 | 6.10 | 1525.0 | +18.3 |
| 48 | 1516.8 | 7.35 | 1526.7 | +9.9 |
| 49 | 1531.9 | 17.05 | 1541.2 | +9.3 |
| 50 | 1562.7 | 8.92 | 1593.9 | +31.2 |
| 51 | 1617.6 | 153.40 | 1642.7 | +25.1 |
| 52 | 1634.4 | 32.49 | 1669.1 | +34.8 |
| 53 | 1661.2 | 17.04 | 1687.7 | +26.5 |
| 54 | 1678.0 | 22.76 | 1721.3 | +43.2 |
| 55 | 3042.8 | 25.15 | 3079.2 | +36.4 |
| 56 | 3093.4 | 17.73 | 3144.4 | +51.0 |
| 57 | 3132.0 | 15.49 | 3179.3 | +47.4 |
| 58 | 3185.3 | 13.75 | 3228.3 | +43.0 |
| 59 | 3203.9 | 22.69 | 3246.3 | +42.4 |
| 60 | 3206.0 | 4.49 | 3248.5 | +42.5 |
| 61 | 3226.5 | 12.14 | 3270.1 | +43.6 |
| 62 | 3250.1 | 0.72 | 3292.8 | +42.6 |
| 63 | 3277.0 | 2.75 | 3321.4 | +44.4 |
Second route
Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 1 cm⁻¹; wb97x max |Δω| 17 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 08:45:31 → 2026-09-29 09:46:45, 3673 s, peak 4.74 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