phenanthrene+vinyl C16H12
A2_25e55c7a83 · SMILES C=Cc1ccc2c(ccc3ccccc32)c1 · InChIKey UIUTYKKZYFMBHJ-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
58 infrared-active bands (500–3500 cm⁻¹); the strongest at 3195 cm⁻¹ (3.1 µm), 53 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)
78 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 | 41.5 | 0.02 | 68.9 | +27.5 |
| 2 | 81.8 | 0.27 | 106.9 | +25.1 |
| 3 | 98.9 | 0.09 | 116.8 | +17.9 |
| 4 | 154.4 | 0.29 | 162.8 | +8.4 |
| 5 | 186.6 | 0.05 | 194.3 | +7.6 |
| 6 | 231.5 | 2.29 | 236.2 | +4.7 |
| 7 | 280.6 | 1.06 | 288.5 | +7.9 |
| 8 | 307.1 | 0.72 | 316.9 | +9.8 |
| 9 | 326.2 | 0.22 | 328.3 | +2.0 |
| 10 | 402.6 | 0.11 | 415.2 | +12.5 |
| 11 | 442.7 | 5.90 | 450.4 | +7.7 |
| 12 | 445.2 | 5.50 | 450.8 | +5.6 |
| 13 | 500.8 | 1.13 | 504.8 | +4.0 |
| 14 | 510.7 | 0.02 | 522.7 | +12.0 |
| 15 | 523.9 | 0.11 | 527.0 | +3.2 |
| 16 | 548.8 | 0.01 | 555.1 | +6.3 |
| 17 | 563.6 | 0.42 | 568.0 | +4.4 |
| 18 | 586.0 | 2.64 | 600.5 | +14.5 |
| 19 | 598.9 | 0.06 | 602.8 | +3.9 |
| 20 | 691.1 | 7.99 | 697.0 | +5.9 |
| 21 | 700.4 | 0.87 | 711.1 | +10.7 |
| 22 | 740.8 | 0.40 | 747.0 | +6.2 |
| 23 | 743.2 | 7.02 | 757.6 | +14.3 |
| 24 | 761.1 | 24.26 | 771.8 | +10.7 |
| 25 | 781.1 | 0.64 | 787.6 | +6.5 |
| 26 | 797.7 | 6.77 | 810.9 | +13.2 |
| 27 | 829.0 | 34.15 | 841.4 | +12.4 |
| 28 | 842.0 | 6.38 | 859.7 | +17.8 |
| 29 | 878.3 | 2.27 | 887.4 | +9.1 |
| 30 | 881.3 | 1.83 | 902.8 | +21.5 |
| 31 | 912.4 | 38.84 | 929.6 | +17.2 |
| 32 | 921.4 | 20.13 | 957.0 | +35.6 |
| 33 | 938.9 | 4.33 | 960.0 | +21.0 |
| 34 | 946.8 | 0.55 | 973.4 | +26.6 |
| 35 | 954.0 | 0.44 | 986.1 | +32.1 |
| 36 | 973.5 | 0.01 | 1005.5 | +32.1 |
| 37 | 985.8 | 0.02 | 1016.5 | +30.7 |
| 38 | 1015.5 | 1.23 | 1023.1 | +7.6 |
| 39 | 1035.2 | 14.00 | 1055.1 | +20.0 |
| 40 | 1056.6 | 6.90 | 1059.5 | +2.9 |
| 41 | 1070.3 | 2.14 | 1079.4 | +9.1 |
| 42 | 1124.9 | 0.39 | 1136.2 | +11.3 |
| 43 | 1181.5 | 1.44 | 1170.3 | -11.2 |
| 44 | 1195.3 | 0.20 | 1192.1 | -3.3 |
| 45 | 1200.2 | 0.87 | 1206.5 | +6.3 |
| 46 | 1215.6 | 2.73 | 1211.3 | -4.3 |
| 47 | 1240.9 | 2.75 | 1240.0 | -1.0 |
| 48 | 1267.1 | 2.64 | 1275.1 | +7.9 |
| 49 | 1292.8 | 8.77 | 1304.7 | +11.8 |
| 50 | 1313.6 | 0.65 | 1318.0 | +4.4 |
| 51 | 1342.5 | 1.55 | 1350.3 | +7.9 |
| 52 | 1348.2 | 2.78 | 1352.6 | +4.5 |
| 53 | 1388.5 | 0.52 | 1371.0 | -17.5 |
| 54 | 1392.5 | 0.94 | 1391.0 | -1.5 |
| 55 | 1431.2 | 3.55 | 1446.5 | +15.3 |
| 56 | 1467.5 | 0.33 | 1478.7 | +11.1 |
| 57 | 1471.7 | 4.67 | 1479.6 | +7.9 |
| 58 | 1485.6 | 0.51 | 1499.0 | +13.4 |
| 59 | 1514.7 | 11.34 | 1527.9 | +13.2 |
| 60 | 1545.8 | 6.25 | 1569.2 | +23.3 |
| 61 | 1581.2 | 1.21 | 1609.9 | +28.6 |
| 62 | 1619.9 | 1.14 | 1653.1 | +33.2 |
| 63 | 1657.8 | 3.31 | 1684.1 | +26.3 |
| 64 | 1672.4 | 2.08 | 1710.2 | +37.8 |
| 65 | 1677.9 | 1.85 | 1725.5 | +47.6 |
| 66 | 1711.9 | 15.59 | 1748.5 | +36.6 |
| 67 | 3150.0 | 17.01 | 3194.1 | +44.1 |
| 68 | 3171.0 | 15.68 | 3212.7 | +41.7 |
| 69 | 3172.4 | 4.21 | 3215.8 | +43.4 |
| 70 | 3175.6 | 5.76 | 3219.6 | +44.0 |
| 71 | 3178.4 | 5.74 | 3221.5 | +43.1 |
| 72 | 3188.3 | 7.18 | 3231.9 | +43.5 |
| 73 | 3195.0 | 39.04 | 3238.7 | +43.7 |
| 74 | 3195.7 | 14.08 | 3240.1 | +44.4 |
| 75 | 3204.2 | 17.52 | 3248.0 | +43.8 |
| 76 | 3211.2 | 17.33 | 3255.4 | +44.2 |
| 77 | 3222.7 | 28.12 | 3268.2 | +45.5 |
| 78 | 3249.6 | 17.70 | 3294.2 | +44.6 |
Second route
Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 3 cm⁻¹; wb97x max |Δω| 19 cm⁻¹.
Provenance
- Releases: layerA2_2026-09-23, layerA2_2026-09-23b, layerA2_2026-09-24
- Entered the corpus as: substituted three- and four-ring cores, enumerated from the parents (layer A′) (layer A2)
- Run: ubuntu-32gb-hel1-12, 2026-09-21 11:13:19 → 2026-09-21 12:54:18, 6059 s, peak 6.23 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