fluorene+ethynyl C15H10
A2_16521f2764 · SMILES C#CC1c2ccccc2-c2ccccc21 · InChIKey NRCHDHDHZQLAIM-UHFFFAOYSA-N
Infrared spectrum at the cheap level (B3LYP/6-31G*, the pipeline's input)
How to read this
38 infrared-active bands (500–3500 cm⁻¹); the strongest at 757 cm⁻¹ (13.2 µm), 79 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 | 62.9 | 0.03 | 84.0 | +21.1 |
| 2 | 100.8 | 0.01 | 118.7 | +17.9 |
| 3 | 109.2 | 1.38 | 121.8 | +12.6 |
| 4 | 144.7 | 0.02 | 157.3 | +12.6 |
| 5 | 209.3 | 0.27 | 213.4 | +4.1 |
| 6 | 279.0 | 0.58 | 292.3 | +13.3 |
| 7 | 285.8 | 0.26 | 298.1 | +12.3 |
| 8 | 402.4 | 2.81 | 412.1 | +9.7 |
| 9 | 404.1 | 0.35 | 419.5 | +15.4 |
| 10 | 424.5 | 0.56 | 431.2 | +6.7 |
| 11 | 445.0 | 3.20 | 454.6 | +9.7 |
| 12 | 454.2 | 0.02 | 460.3 | +6.1 |
| 13 | 513.0 | 1.91 | 522.7 | +9.7 |
| 14 | 519.7 | 0.63 | 524.1 | +4.4 |
| 15 | 574.3 | 0.04 | 586.8 | +12.5 |
| 16 | 611.6 | 39.09 | 635.1 | +23.5 |
| 17 | 617.3 | 23.69 | 643.5 | +26.3 |
| 18 | 631.0 | 0.77 | 660.8 | +29.9 |
| 19 | 640.8 | 21.74 | 677.2 | +36.4 |
| 20 | 669.4 | 10.58 | 684.2 | +14.8 |
| 21 | 729.1 | 0.13 | 741.3 | +12.3 |
| 22 | 753.6 | 0.07 | 766.9 | +13.3 |
| 23 | 757.3 | 79.34 | 768.4 | +11.1 |
| 24 | 774.5 | 15.38 | 782.7 | +8.2 |
| 25 | 798.9 | 0.33 | 813.3 | +14.4 |
| 26 | 846.7 | 0.37 | 860.7 | +14.0 |
| 27 | 862.4 | 2.08 | 876.0 | +13.6 |
| 28 | 889.6 | 0.12 | 909.1 | +19.5 |
| 29 | 893.1 | 1.05 | 913.4 | +20.3 |
| 30 | 942.4 | 0.23 | 972.7 | +30.3 |
| 31 | 944.9 | 1.68 | 973.9 | +29.0 |
| 32 | 980.2 | 0.05 | 1013.0 | +32.8 |
| 33 | 982.4 | 0.03 | 1014.5 | +32.1 |
| 34 | 1013.3 | 3.89 | 1031.2 | +17.9 |
| 35 | 1026.1 | 1.03 | 1034.6 | +8.5 |
| 36 | 1054.0 | 0.75 | 1061.7 | +7.7 |
| 37 | 1060.5 | 3.74 | 1065.7 | +5.2 |
| 38 | 1126.4 | 1.15 | 1134.2 | +7.8 |
| 39 | 1135.7 | 0.01 | 1144.2 | +8.5 |
| 40 | 1184.2 | 0.10 | 1183.1 | -1.1 |
| 41 | 1189.6 | 0.06 | 1185.8 | -3.8 |
| 42 | 1197.2 | 1.80 | 1206.1 | +9.0 |
| 43 | 1205.0 | 0.24 | 1216.2 | +11.1 |
| 44 | 1206.9 | 0.80 | 1225.7 | +18.8 |
| 45 | 1259.4 | 3.67 | 1258.4 | -1.0 |
| 46 | 1312.4 | 7.81 | 1320.5 | +8.1 |
| 47 | 1325.7 | 2.59 | 1332.6 | +6.9 |
| 48 | 1334.4 | 1.43 | 1332.9 | -1.5 |
| 49 | 1353.6 | 6.54 | 1343.8 | -9.8 |
| 50 | 1396.4 | 0.23 | 1380.0 | -16.4 |
| 51 | 1491.9 | 10.84 | 1506.0 | +14.2 |
| 52 | 1498.2 | 21.16 | 1508.9 | +10.7 |
| 53 | 1525.7 | 7.50 | 1540.0 | +14.2 |
| 54 | 1526.8 | 0.31 | 1552.0 | +25.2 |
| 55 | 1637.4 | 1.08 | 1668.7 | +31.3 |
| 56 | 1642.4 | 0.08 | 1677.1 | +34.7 |
| 57 | 1662.9 | 1.11 | 1700.6 | +37.7 |
| 58 | 1663.4 | 2.38 | 1709.5 | +46.1 |
| 59 | 2236.8 | 4.02 | 2269.5 | +32.7 |
| 60 | 2992.7 | 7.58 | 3048.5 | +55.8 |
| 61 | 3180.8 | 3.47 | 3224.2 | +43.3 |
| 62 | 3182.2 | 0.28 | 3224.9 | +42.7 |
| 63 | 3188.7 | 5.19 | 3232.1 | +43.4 |
| 64 | 3190.1 | 0.16 | 3232.1 | +42.1 |
| 65 | 3197.9 | 1.01 | 3241.1 | +43.1 |
| 66 | 3199.0 | 52.07 | 3241.7 | +42.7 |
| 67 | 3208.6 | 59.21 | 3251.3 | +42.8 |
| 68 | 3209.7 | 5.59 | 3253.5 | +43.8 |
| 69 | 3495.3 | 67.18 | 3531.3 | +36.0 |
Second route
Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 6 cm⁻¹; wb97x max |Δω| 8 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-hel1-9, 2026-09-21 01:00:31 → 2026-09-21 02:18:40, 4688 s, peak 5.74 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