naphthalene+OCH3+OCH3 C12H12O2

B_32502b56fd · SMILES COc1ccc2c(OC)cccc2c1 · InChIKey RBUFUWIWCCOVOS-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

48 infrared-active bands (500–3500 cm⁻¹); the strongest at 1268 cm⁻¹ (7.9 µm), 275 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 — 2026-09-29, ubuntu-32gb-hel1-16
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)

72 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	58.2	4.36	69.5	+11.3
2	95.7	0.23	114.4	+18.7
3	136.6	0.03	149.5	+12.9
4	150.8	6.45	163.7	+12.9
5	165.3	1.90	172.4	+7.2
6	229.7	0.11	223.1	-6.6
7	233.1	2.31	239.6	+6.4
8	250.1	0.14	244.7	-5.5
9	292.3	0.01	298.0	+5.7
10	322.6	0.61	327.4	+4.8
11	329.5	1.15	338.0	+8.5
12	437.5	1.55	444.7	+7.2
13	439.4	7.32	451.8	+12.4
14	451.6	2.66	455.3	+3.7
15	512.5	3.25	516.5	+4.0
16	528.1	0.37	539.2	+11.0
17	540.3	0.60	545.8	+5.5
18	613.6	7.83	619.3	+5.7
19	625.3	2.43	641.4	+16.1
20	655.1	0.27	670.2	+15.1
21	710.5	5.70	716.0	+5.5
22	743.5	10.35	751.2	+7.7
23	754.8	9.22	768.7	+13.9
24	788.9	25.84	807.2	+18.4
25	841.9	26.20	855.4	+13.5
26	846.7	23.05	856.6	+10.0
27	848.4	7.34	870.5	+22.2
28	872.4	14.23	897.8	+25.4
29	958.9	0.99	974.7	+15.9
30	963.0	20.24	990.0	+27.0
31	970.6	0.04	1003.9	+33.4
32	1019.4	5.40	1032.0	+12.6
33	1077.3	76.35	1097.0	+19.8
34	1105.0	14.00	1113.8	+8.9
35	1141.6	25.22	1150.2	+8.6
36	1176.8	44.64	1181.0	+4.2
37	1185.7	0.88	1186.7	+1.0
38	1185.9	0.79	1189.4	+3.5
39	1203.7	44.07	1202.5	-1.2
40	1212.7	0.89	1214.5	+1.7
41	1228.9	2.15	1230.4	+1.5
42	1236.5	41.36	1238.0	+1.5
43	1268.0	274.71	1271.0	+2.9
44	1302.1	100.85	1307.8	+5.8
45	1310.6	70.11	1324.2	+13.7
46	1399.0	1.22	1400.3	+1.3
47	1419.5	62.48	1423.7	+4.2
48	1423.7	68.02	1431.3	+7.6
49	1483.8	128.23	1494.6	+10.8
50	1491.2	38.30	1496.2	+5.0
51	1509.5	45.00	1516.6	+7.1
52	1519.3	4.76	1521.9	+2.6
53	1519.5	6.06	1526.3	+6.8
54	1524.7	21.67	1539.6	+14.9
55	1534.8	8.83	1541.2	+6.4
56	1536.8	22.18	1542.7	+5.8
57	1565.2	7.92	1594.5	+29.3
58	1637.2	69.66	1670.4	+33.2
59	1659.2	68.66	1685.5	+26.3
60	1683.6	125.64	1727.2	+43.6
61	3024.8	59.05	3060.8	+36.1
62	3026.9	57.30	3062.9	+36.0
63	3083.1	42.83	3131.5	+48.4
64	3086.0	43.50	3134.5	+48.6
65	3156.3	27.36	3199.6	+43.3
66	3156.5	28.25	3199.7	+43.2
67	3180.3	3.01	3224.1	+43.9
68	3198.0	30.21	3241.8	+43.8
69	3210.1	3.93	3253.5	+43.4
70	3215.9	14.75	3260.8	+44.8
71	3228.8	14.19	3273.5	+44.8
72	3232.5	6.33	3276.5	+44.0

Second route

Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 1 cm⁻¹; wb97x max |Δω| 16 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-hel1-16, 2026-09-29 00:19:25 → 2026-09-29 01:33:31, 4445 s, peak 5.11 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