biphenyl C12H10
A_fdc27f1bd1 · SMILES c1ccc(-c2ccccc2)cc1 · InChIKey ZUOUZKKEUPVFJK-UHFFFAOYSA-N
Infrared spectrum at the cheap level (B3LYP/6-31G*, the pipeline's input)
How to read this
28 infrared-active bands (500–3500 cm⁻¹); the strongest at 756 cm⁻¹ (13.2 µm), 70 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)
60 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 | 70.5 | 0.00 | 95.2 | +24.6 |
| 2 | 96.6 | 0.57 | 110.0 | +13.4 |
| 3 | 129.6 | 0.06 | 141.3 | +11.7 |
| 4 | 270.6 | 0.02 | 279.2 | +8.6 |
| 5 | 315.0 | 0.00 | 318.0 | +3.0 |
| 6 | 373.2 | 0.10 | 380.3 | +7.1 |
| 7 | 416.2 | 0.33 | 427.9 | +11.7 |
| 8 | 423.2 | 0.00 | 435.3 | +12.1 |
| 9 | 500.6 | 4.44 | 509.7 | +9.1 |
| 10 | 560.0 | 1.56 | 570.8 | +10.8 |
| 11 | 623.8 | 8.01 | 628.1 | +4.4 |
| 12 | 628.7 | 0.00 | 632.0 | +3.3 |
| 13 | 641.1 | 0.03 | 644.8 | +3.8 |
| 14 | 714.1 | 5.97 | 724.8 | +10.6 |
| 15 | 714.8 | 31.21 | 727.2 | +12.4 |
| 16 | 755.6 | 70.21 | 764.5 | +8.9 |
| 17 | 757.1 | 0.00 | 770.7 | +13.6 |
| 18 | 796.9 | 5.21 | 815.7 | +18.8 |
| 19 | 860.1 | 0.55 | 878.9 | +18.8 |
| 20 | 861.5 | 0.00 | 880.9 | +19.4 |
| 21 | 920.3 | 2.81 | 941.9 | +21.6 |
| 22 | 937.7 | 0.87 | 961.7 | +24.0 |
| 23 | 968.0 | 0.77 | 1000.4 | +32.4 |
| 24 | 970.6 | 0.00 | 1002.6 | +32.0 |
| 25 | 994.8 | 0.22 | 1021.8 | +26.9 |
| 26 | 995.0 | 0.05 | 1024.2 | +29.2 |
| 27 | 1014.8 | 0.41 | 1024.6 | +9.8 |
| 28 | 1020.0 | 0.00 | 1027.4 | +7.4 |
| 29 | 1027.4 | 4.93 | 1038.3 | +10.9 |
| 30 | 1062.1 | 0.00 | 1071.7 | +9.6 |
| 31 | 1074.9 | 2.11 | 1083.1 | +8.2 |
| 32 | 1111.1 | 6.02 | 1120.2 | +9.1 |
| 33 | 1116.0 | 0.35 | 1121.2 | +5.3 |
| 34 | 1192.8 | 0.00 | 1185.5 | -7.4 |
| 35 | 1193.6 | 0.07 | 1185.8 | -7.8 |
| 36 | 1213.6 | 0.59 | 1213.8 | +0.2 |
| 37 | 1221.2 | 0.00 | 1222.5 | +1.3 |
| 38 | 1311.9 | 0.00 | 1290.3 | -21.6 |
| 39 | 1315.2 | 2.59 | 1312.8 | -2.3 |
| 40 | 1348.1 | 0.00 | 1335.2 | -12.9 |
| 41 | 1364.6 | 0.07 | 1364.3 | -0.3 |
| 42 | 1374.0 | 0.85 | 1364.6 | -9.4 |
| 43 | 1477.3 | 7.32 | 1488.0 | +10.7 |
| 44 | 1507.0 | 1.12 | 1518.8 | +11.8 |
| 45 | 1534.8 | 28.77 | 1543.3 | +8.5 |
| 46 | 1556.5 | 0.00 | 1576.1 | +19.6 |
| 47 | 1628.2 | 4.18 | 1659.8 | +31.6 |
| 48 | 1643.5 | 0.11 | 1677.3 | +33.8 |
| 49 | 1661.6 | 0.00 | 1697.8 | +36.2 |
| 50 | 1664.1 | 11.82 | 1705.3 | +41.2 |
| 51 | 3179.0 | 8.98 | 3222.4 | +43.4 |
| 52 | 3179.9 | 0.00 | 3223.0 | +43.1 |
| 53 | 3184.5 | 0.01 | 3228.5 | +44.0 |
| 54 | 3187.5 | 8.47 | 3230.7 | +43.2 |
| 55 | 3194.3 | 32.09 | 3238.5 | +44.2 |
| 56 | 3198.6 | 0.01 | 3241.7 | +43.1 |
| 57 | 3200.4 | 10.25 | 3244.4 | +43.9 |
| 58 | 3204.0 | 58.07 | 3247.1 | +43.1 |
| 59 | 3209.5 | 42.21 | 3252.6 | +43.1 |
| 60 | 3211.1 | 0.01 | 3253.9 | +42.8 |
Second route
Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 0 cm⁻¹; wb97x max |Δω| 4 cm⁻¹.
Provenance
- Releases: layerA2_2026-09-23, layerA2_2026-09-23b, layerA2_2026-09-24, layerA_2026-09-22
- Entered the corpus as: parent molecules chosen by hand (benzene, naphthalene, the PAH cores and their relatives) (layer A)
- Run: Asus18, 2026-09-14 10:11:43 → 2026-09-14 11:51:12, 5968 s, peak 5.42 GB, deck 97ed2d67c66b
- 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