naphthalene+COOH+OCH3 C12H10O3

B_6216abc398 · SMILES COc1cc(C(=O)O)cc2ccccc12 · InChIKey ZXDDPENMDIVYGR-UHFFFAOYSA-N

Cheap level done

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)

cheap input (B3LYP) bands

How to read this

46 infrared-active bands (500–3500 cm⁻¹); the strongest at 1194 cm⁻¹ (8.4 µm), 314 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-hel1-18
Correction predicted — not yet: the learned layer is training
Spectrum predicted — not yet: the learned layer is training
Anchored
Validated

Request a run

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)

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	58.5	0.77	92.3	+33.8
2	85.4	4.71	110.8	+25.3
3	90.3	0.18	116.2	+25.9
4	148.5	0.17	161.2	+12.7
5	163.7	0.77	181.8	+18.1
6	192.2	0.06	207.1	+14.9
7	206.2	3.10	215.0	+8.8
8	259.4	0.02	289.2	+29.8
9	306.5	0.27	323.5	+17.0
10	324.9	3.22	331.6	+6.7
11	337.9	2.24	344.6	+6.7
12	425.3	0.20	432.4	+7.1
13	442.7	0.59	455.1	+12.4
14	488.6	4.87	503.7	+15.0
15	508.9	0.96	515.5	+6.5
16	533.1	0.98	538.1	+5.0
17	571.2	34.91	588.9	+17.6
18	587.6	34.00	594.0	+6.4
19	630.6	18.13	639.0	+8.4
20	634.2	7.91	652.3	+18.0
21	656.0	47.51	683.3	+27.2
22	680.8	52.25	691.9	+11.1
23	763.9	0.30	776.9	+13.0
24	779.0	4.47	786.7	+7.7
25	783.2	71.41	800.8	+17.6
26	791.5	21.35	806.6	+15.1
27	872.0	7.69	881.9	+9.9
28	880.5	0.06	888.3	+7.7
29	883.6	4.14	904.1	+20.5
30	924.6	12.49	950.7	+26.1
31	947.7	8.26	957.8	+10.0
32	966.1	3.03	999.4	+33.3
33	995.7	0.01	1027.7	+32.0
34	1023.6	2.01	1037.4	+13.8
35	1056.0	2.99	1067.2	+11.2
36	1129.6	15.70	1139.7	+10.1
37	1147.7	61.14	1158.8	+11.1
38	1179.8	193.44	1174.4	-5.4
39	1185.4	1.17	1196.5	+11.1
40	1193.5	314.47	1207.0	+13.5
41	1200.0	65.59	1224.7	+24.7
42	1227.5	7.24	1231.6	+4.2
43	1249.7	16.78	1246.2	-3.5
44	1276.3	38.32	1279.8	+3.6
45	1313.0	90.72	1320.1	+7.2
46	1378.4	85.73	1376.4	-2.1
47	1401.5	59.24	1417.6	+16.0
48	1418.2	31.60	1427.3	+9.1
49	1446.7	105.21	1457.3	+10.7
50	1473.4	11.72	1487.6	+14.2
51	1502.1	26.45	1515.6	+13.5
52	1509.9	24.04	1525.5	+15.6
53	1519.9	6.02	1532.4	+12.5
54	1535.2	26.92	1546.0	+10.8
55	1562.1	31.75	1590.4	+28.3
56	1631.9	58.67	1664.6	+32.8
57	1654.1	43.57	1680.8	+26.6
58	1680.6	11.01	1728.0	+47.4
59	1818.5	303.36	1852.5	+34.0
60	3031.3	53.52	3067.1	+35.8
61	3092.5	37.68	3140.4	+47.9
62	3161.1	22.28	3204.1	+43.1
63	3183.7	0.14	3226.6	+42.9
64	3193.8	15.61	3236.7	+42.9
65	3207.8	29.31	3250.5	+42.8
66	3220.2	0.58	3263.6	+43.4
67	3232.8	7.86	3276.7	+43.9
68	3260.9	3.71	3306.2	+45.3
69	3698.2	80.43	3738.4	+40.2

Second route

Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 1 cm⁻¹; wb97x max |Δω| 21 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-hel1-18, 2026-09-30 09:08:52 → 2026-09-30 10:29:13, 4821 s, peak 5.36 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