acenaphthylene+CHO C13H8O

A2_3a4d58eb26 · SMILES O=Cc1ccc2cccc3c2c1C=C3 · InChIKey QBZMKCYBYMNCBL-UHFFFAOYSA-N

Cheap level done analytic check agrees

Infrared spectrum at the cheap level (B3LYP/6-31G*, the pipeline's input)

cheap input (B3LYP) bands

How to read this

30 infrared-active bands (500–3500 cm⁻¹); the strongest at 1789 cm⁻¹ (5.6 µm), 320 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 %).

Structure

2D depiction from the SMILES.

Status ladder

Listed
Cheap level done — 2026-09-22, ubuntu-32gb-hel1-12
Correction predicted — not yet: the learned layer is training
Spectrum predicted — not yet: the learned layer is training
Anchored
Validated

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Not available on this site yet: the pipeline (a molecule in, its spectrum and certificate out) runs on the project's own computer, with three of the four mode families licensed at the DFT stand-in level. Sign-in will be needed only to request runs; reading stays open.

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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	78.1	0.98	95.1	+17.0
2	165.0	9.18	185.7	+20.7
3	177.5	4.71	187.9	+10.4
4	199.9	3.07	210.8	+10.9
5	227.4	2.07	229.6	+2.2
6	285.8	1.79	293.6	+7.8
7	358.8	0.98	362.6	+3.8
8	390.9	0.00	402.8	+11.9
9	435.6	12.04	442.6	+7.1
10	483.6	4.30	487.8	+4.2
11	500.4	0.96	510.7	+10.4
12	528.6	1.06	533.1	+4.5
13	583.5	0.10	596.0	+12.5
14	610.9	0.59	616.3	+5.4
15	624.3	0.00	625.6	+1.3
16	674.9	0.79	682.4	+7.5
17	703.2	3.60	713.7	+10.5
18	719.0	0.12	723.1	+4.1
19	746.6	33.60	748.0	+1.4
20	774.7	56.83	783.9	+9.3
21	780.0	6.86	796.8	+16.8
22	832.4	5.09	842.2	+9.8
23	862.8	50.57	874.9	+12.1
24	867.5	6.53	877.1	+9.6
25	920.7	0.05	946.5	+25.8
26	935.0	0.74	963.7	+28.7
27	964.8	8.54	969.9	+5.1
28	973.8	1.30	1009.3	+35.5
29	985.1	0.02	1018.3	+33.2
30	1020.9	0.06	1038.2	+17.3
31	1030.2	1.47	1046.3	+16.1
32	1057.6	0.89	1063.2	+5.6
33	1118.2	8.78	1122.2	+4.0
34	1129.9	8.46	1137.3	+7.5
35	1186.8	0.22	1178.9	-7.9
36	1210.1	7.87	1216.6	+6.6
37	1246.3	14.55	1246.1	-0.2
38	1257.0	67.42	1276.3	+19.3
39	1268.0	1.45	1277.4	+9.4
40	1352.7	2.39	1349.0	-3.7
41	1370.0	14.63	1391.9	+21.9
42	1432.4	1.02	1433.7	+1.3
43	1436.6	2.54	1441.0	+4.4
44	1464.4	7.33	1477.6	+13.2
45	1472.5	48.60	1481.3	+8.7
46	1499.2	21.87	1522.7	+23.5
47	1532.3	0.47	1561.6	+29.3
48	1557.7	11.51	1581.9	+24.2
49	1640.7	0.11	1678.6	+37.8
50	1667.2	17.13	1702.4	+35.2
51	1672.1	2.94	1713.1	+41.0
52	1789.0	320.06	1824.2	+35.1
53	2936.1	107.59	2986.2	+50.1
54	3184.4	0.52	3227.3	+42.8
55	3191.5	3.24	3234.2	+42.7
56	3194.2	21.20	3236.6	+42.4
57	3207.7	32.61	3249.9	+42.2
58	3221.0	6.24	3264.3	+43.3
59	3232.3	2.01	3273.7	+41.4
60	3252.4	12.35	3293.6	+41.2

Second route

Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 2 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-hel1-12, 2026-09-22 06:58:48 → 2026-09-22 07:57:53, 3545 s, peak 4.59 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