naphthalene+CH3+CHO C12H10O

B_55aa555efc · SMILES O=CCc1ccc2ccccc2c1 · InChIKey ZONWDLKOOMKAKI-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

40 infrared-active bands (500–3500 cm⁻¹); the strongest at 2892 cm⁻¹ (3.5 µm), 219 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 — 2026-09-30, ubuntu-32gb-hel1-21
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)

63 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	35.9	1.87	57.2	+21.3
2	82.0	4.26	99.2	+17.2
3	121.1	4.07	158.0	+36.8
4	157.3	2.42	175.2	+17.9
5	188.2	1.55	194.9	+6.7
6	251.0	1.45	256.4	+5.4
7	300.6	1.74	309.8	+9.2
8	399.6	3.58	404.3	+4.7
9	404.5	0.50	416.0	+11.4
10	437.4	7.55	443.0	+5.6
11	491.7	8.85	497.2	+5.5
12	514.7	0.78	525.2	+10.5
13	526.6	0.14	530.4	+3.9
14	624.4	0.93	632.2	+7.8
15	634.5	1.21	644.1	+9.6
16	678.1	9.17	683.9	+5.8
17	718.2	0.28	730.9	+12.6
18	757.6	12.64	768.4	+10.8
19	779.9	6.82	791.7	+11.8
20	785.2	0.57	795.0	+9.8
21	810.0	35.28	820.8	+10.7
22	841.7	5.72	854.7	+13.0
23	869.5	13.42	880.6	+11.2
24	878.5	7.55	894.8	+16.3
25	912.0	6.59	931.2	+19.2
26	942.2	13.21	954.4	+12.2
27	953.8	1.31	983.6	+29.8
28	965.0	1.85	989.1	+24.1
29	979.4	11.18	995.2	+15.8
30	989.4	0.01	1019.7	+30.3
31	1047.0	6.51	1059.0	+12.0
32	1052.1	0.21	1063.3	+11.2
33	1157.8	1.81	1157.9	+0.1
34	1187.2	0.71	1164.8	-22.3
35	1190.5	1.35	1189.8	-0.7
36	1206.4	1.82	1208.9	+2.4
37	1228.5	2.76	1234.1	+5.6
38	1252.9	0.82	1255.6	+2.7
39	1288.2	0.47	1292.2	+3.9
40	1300.2	5.93	1305.6	+5.4
41	1347.7	20.48	1372.1	+24.4
42	1408.5	1.91	1402.0	-6.5
43	1414.8	2.71	1415.8	+1.0
44	1424.4	5.38	1430.3	+5.9
45	1437.5	18.19	1450.0	+12.5
46	1472.9	16.25	1484.7	+11.8
47	1490.8	1.86	1503.4	+12.6
48	1522.0	0.09	1536.6	+14.6
49	1564.0	9.06	1590.3	+26.3
50	1628.2	0.18	1659.8	+31.6
51	1664.2	5.95	1691.2	+27.0
52	1691.8	1.99	1738.1	+46.3
53	1841.0	129.79	1873.1	+32.1
54	2891.7	218.72	2941.3	+49.6
55	3001.8	38.78	3048.6	+46.8
56	3059.2	12.84	3109.6	+50.4
57	3169.0	13.38	3213.8	+44.9
58	3176.3	6.72	3219.6	+43.3
59	3180.0	4.90	3224.0	+44.0
60	3182.8	3.73	3225.8	+43.1
61	3194.5	34.59	3237.6	+43.1
62	3206.6	32.50	3249.8	+43.3
63	3208.2	17.90	3251.1	+42.9

Second route

Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 6 cm⁻¹; wb97x max |Δω| 9 cm⁻¹.

Provenance

Releases: none yet
Entered the corpus as: cores with one or two substituents, enumerated from the parents (layer B)
Run: ubuntu-32gb-hel1-21, 2026-09-30 07:43:25 → 2026-09-30 08:42:51, 3565 s, peak 4.47 GB, deck 9e27bf8e9348
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