carbazole+COOH C13H9NO2
A2_1e3ee2b3a8 · SMILES O=C(O)c1ccc2[nH]c3ccccc3c2c1 · InChIKey UZRJWXGXZKPSJO-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
42 infrared-active bands (500–3500 cm⁻¹); the strongest at 1202 cm⁻¹ (8.3 µm), 424 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)
69 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 | 59.7 | 1.93 | 88.3 | +28.6 |
| 2 | 78.9 | 0.36 | 105.5 | +26.6 |
| 3 | 125.0 | 2.00 | 135.4 | +10.5 |
| 4 | 128.0 | 0.73 | 137.3 | +9.3 |
| 5 | 193.1 | 0.01 | 205.3 | +12.1 |
| 6 | 248.2 | 0.28 | 256.3 | +8.1 |
| 7 | 298.3 | 3.96 | 309.0 | +10.7 |
| 8 | 320.2 | 1.81 | 322.7 | +2.6 |
| 9 | 328.2 | 15.13 | 343.7 | +15.5 |
| 10 | 380.2 | 74.30 | 414.5 | +34.3 |
| 11 | 435.4 | 3.89 | 447.0 | +11.5 |
| 12 | 455.9 | 0.01 | 464.4 | +8.6 |
| 13 | 468.1 | 1.94 | 473.3 | +5.2 |
| 14 | 478.6 | 5.13 | 484.4 | +5.8 |
| 15 | 551.0 | 11.41 | 555.5 | +4.5 |
| 16 | 554.8 | 59.51 | 578.8 | +24.0 |
| 17 | 580.1 | 0.03 | 595.9 | +15.8 |
| 18 | 597.0 | 39.61 | 603.5 | +6.5 |
| 19 | 634.5 | 37.77 | 643.6 | +9.1 |
| 20 | 639.5 | 3.09 | 668.8 | +29.2 |
| 21 | 660.2 | 48.51 | 669.2 | +9.0 |
| 22 | 737.8 | 10.93 | 746.0 | +8.3 |
| 23 | 740.6 | 62.91 | 758.6 | +18.0 |
| 24 | 759.9 | 9.78 | 776.1 | +16.2 |
| 25 | 772.5 | 51.85 | 793.6 | +21.1 |
| 26 | 790.3 | 9.39 | 807.1 | +16.8 |
| 27 | 814.5 | 1.70 | 822.8 | +8.3 |
| 28 | 831.5 | 8.93 | 850.9 | +19.4 |
| 29 | 862.7 | 0.03 | 877.1 | +14.4 |
| 30 | 868.2 | 3.55 | 889.1 | +20.9 |
| 31 | 908.7 | 1.31 | 916.9 | +8.2 |
| 32 | 929.6 | 1.26 | 964.3 | +34.7 |
| 33 | 942.7 | 3.44 | 968.0 | +25.2 |
| 34 | 956.0 | 1.41 | 984.8 | +28.8 |
| 35 | 971.0 | 0.01 | 1002.8 | +31.8 |
| 36 | 1034.4 | 4.35 | 1041.8 | +7.4 |
| 37 | 1050.2 | 8.53 | 1060.5 | +10.3 |
| 38 | 1111.4 | 52.83 | 1124.0 | +12.7 |
| 39 | 1144.3 | 18.04 | 1152.1 | +7.8 |
| 40 | 1168.0 | 59.90 | 1168.0 | -0.0 |
| 41 | 1187.6 | 23.15 | 1183.5 | -4.1 |
| 42 | 1202.0 | 423.62 | 1232.2 | +30.2 |
| 43 | 1237.1 | 25.11 | 1243.9 | +6.8 |
| 44 | 1249.2 | 2.67 | 1260.9 | +11.7 |
| 45 | 1269.5 | 84.03 | 1277.1 | +7.6 |
| 46 | 1319.8 | 38.38 | 1319.3 | -0.4 |
| 47 | 1325.9 | 10.23 | 1333.0 | +7.0 |
| 48 | 1366.9 | 51.18 | 1353.8 | -13.1 |
| 49 | 1386.0 | 37.58 | 1363.8 | -22.3 |
| 50 | 1391.9 | 175.98 | 1411.5 | +19.6 |
| 51 | 1447.9 | 34.83 | 1450.2 | +2.3 |
| 52 | 1493.1 | 35.97 | 1509.7 | +16.6 |
| 53 | 1505.5 | 14.40 | 1522.4 | +16.9 |
| 54 | 1528.4 | 1.09 | 1549.7 | +21.3 |
| 55 | 1542.3 | 22.24 | 1564.1 | +21.9 |
| 56 | 1628.1 | 0.91 | 1659.0 | +30.8 |
| 57 | 1637.9 | 9.47 | 1670.6 | +32.6 |
| 58 | 1662.3 | 126.15 | 1696.7 | +34.4 |
| 59 | 1680.3 | 26.89 | 1726.5 | +46.2 |
| 60 | 1813.0 | 309.68 | 1847.0 | +34.0 |
| 61 | 3184.8 | 1.34 | 3227.7 | +42.9 |
| 62 | 3191.4 | 2.26 | 3234.3 | +42.8 |
| 63 | 3195.8 | 13.02 | 3238.9 | +43.2 |
| 64 | 3201.0 | 28.23 | 3244.0 | +43.0 |
| 65 | 3213.4 | 26.89 | 3255.9 | +42.5 |
| 66 | 3222.2 | 1.73 | 3264.8 | +42.7 |
| 67 | 3235.5 | 2.45 | 3279.1 | +43.7 |
| 68 | 3660.3 | 60.47 | 3707.2 | +47.0 |
| 69 | 3701.4 | 80.45 | 3741.7 | +40.3 |
Second route
Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 2 cm⁻¹; wb97x max |Δω| 16 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-hel1-11, 2026-09-21 12:38:03 → 2026-09-21 14:07:14, 5350 s, peak 5.88 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