biphenyl+CHO C13H10O
B_32a4ec61cd · SMILES O=Cc1ccccc1-c1ccccc1 · InChIKey LCRCBXLHWTVPEQ-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
40 infrared-active bands (500–3500 cm⁻¹); the strongest at 1789 cm⁻¹ (5.6 µm), 221 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 | -42.0 | 0.31 | -13.1 | +28.9 |
| 2 | 77.3 | 0.51 | 87.6 | +10.3 |
| 3 | 87.2 | 0.02 | 105.8 | +18.6 |
| 4 | 118.8 | 4.01 | 143.9 | +25.2 |
| 5 | 207.3 | 4.32 | 212.2 | +4.9 |
| 6 | 208.0 | 5.21 | 215.7 | +7.7 |
| 7 | 288.2 | 0.09 | 293.8 | +5.6 |
| 8 | 318.6 | 0.73 | 325.7 | +7.1 |
| 9 | 319.6 | 5.26 | 326.2 | +6.6 |
| 10 | 412.3 | 0.00 | 422.1 | +9.8 |
| 11 | 452.2 | 0.96 | 459.5 | +7.2 |
| 12 | 461.0 | 2.56 | 470.3 | +9.3 |
| 13 | 555.4 | 3.82 | 567.8 | +12.3 |
| 14 | 566.1 | 1.30 | 574.0 | +7.9 |
| 15 | 630.4 | 2.63 | 634.1 | +3.7 |
| 16 | 634.0 | 0.05 | 637.5 | +3.5 |
| 17 | 654.6 | 17.69 | 660.0 | +5.4 |
| 18 | 717.1 | 23.59 | 726.1 | +9.0 |
| 19 | 754.9 | 2.95 | 769.8 | +14.9 |
| 20 | 762.4 | 8.91 | 771.0 | +8.6 |
| 21 | 780.6 | 19.91 | 797.1 | +16.5 |
| 22 | 784.4 | 36.23 | 798.1 | +13.7 |
| 23 | 841.4 | 25.04 | 852.0 | +10.6 |
| 24 | 862.8 | 0.01 | 878.1 | +15.3 |
| 25 | 902.7 | 0.01 | 922.0 | +19.3 |
| 26 | 931.6 | 2.02 | 952.7 | +21.1 |
| 27 | 968.3 | 0.00 | 998.7 | +30.4 |
| 28 | 973.6 | 1.13 | 1000.2 | +26.6 |
| 29 | 998.3 | 0.08 | 1024.5 | +26.2 |
| 30 | 1002.8 | 0.03 | 1025.9 | +23.1 |
| 31 | 1017.8 | 2.42 | 1031.0 | +13.2 |
| 32 | 1026.0 | 6.36 | 1036.6 | +10.7 |
| 33 | 1032.3 | 0.03 | 1047.7 | +15.4 |
| 34 | 1063.4 | 0.42 | 1072.1 | +8.7 |
| 35 | 1075.5 | 0.22 | 1083.3 | +7.8 |
| 36 | 1109.3 | 3.19 | 1115.5 | +6.3 |
| 37 | 1126.7 | 8.36 | 1136.3 | +9.7 |
| 38 | 1193.8 | 0.07 | 1184.8 | -9.0 |
| 39 | 1194.5 | 2.73 | 1187.3 | -7.2 |
| 40 | 1213.9 | 0.58 | 1213.1 | -0.8 |
| 41 | 1225.7 | 35.30 | 1237.8 | +12.1 |
| 42 | 1284.7 | 42.03 | 1297.8 | +13.2 |
| 43 | 1315.0 | 4.04 | 1300.7 | -14.3 |
| 44 | 1329.0 | 0.14 | 1304.7 | -24.4 |
| 45 | 1345.8 | 3.62 | 1335.4 | -10.4 |
| 46 | 1363.3 | 0.31 | 1359.0 | -4.3 |
| 47 | 1442.8 | 25.01 | 1448.5 | +5.6 |
| 48 | 1488.1 | 4.91 | 1499.6 | +11.5 |
| 49 | 1490.2 | 9.16 | 1504.6 | +14.4 |
| 50 | 1521.6 | 15.01 | 1534.7 | +13.1 |
| 51 | 1548.6 | 2.46 | 1568.2 | +19.5 |
| 52 | 1623.5 | 1.67 | 1657.6 | +34.1 |
| 53 | 1634.9 | 1.39 | 1668.7 | +33.8 |
| 54 | 1652.9 | 43.35 | 1690.7 | +37.9 |
| 55 | 1662.3 | 4.10 | 1702.6 | +40.3 |
| 56 | 1788.8 | 221.28 | 1822.2 | +33.4 |
| 57 | 2977.9 | 95.08 | 3027.9 | +50.0 |
| 58 | 3182.0 | 2.06 | 3225.0 | +42.9 |
| 59 | 3186.3 | 1.18 | 3228.9 | +42.6 |
| 60 | 3187.6 | 0.09 | 3230.7 | +43.2 |
| 61 | 3196.3 | 15.58 | 3239.3 | +43.0 |
| 62 | 3198.7 | 10.08 | 3241.3 | +42.6 |
| 63 | 3202.8 | 33.83 | 3245.8 | +43.0 |
| 64 | 3208.3 | 18.85 | 3250.8 | +42.5 |
| 65 | 3212.2 | 19.55 | 3254.8 | +42.6 |
| 66 | 3220.0 | 10.90 | 3263.2 | +43.2 |
Second route
Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 1 cm⁻¹; wb97x max |Δω| 15 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-hel1-21, 2026-09-29 04:37:18 → 2026-09-29 05:42:41, 3922 s, peak 4.95 GB, deck 9e27bf8e9348
- Imaginary modes: B3LYP 1, ωB97X 1
- Cheap-level band heights: dipole derivatives dipole_b3lyp_cphf.npz, Hessian hessian_b3lyp.npz
- Source files: corpus factory · manifest