carbazole+COOH C13H9NO2

A2_253cbb1c94 · SMILES O=C(O)c1ccc2c(c1)[nH]c1ccccc12 · InChIKey SNHLDNRYSKNZRC-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

45 infrared-active bands (500–3500 cm⁻¹); the strongest at 1194 cm⁻¹ (8.4 µm), 363 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 — 2026-09-21, 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)

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	59.9	0.62	71.9	+12.1
2	63.3	1.47	98.6	+35.3
3	137.8	1.40	146.8	+9.0
4	144.4	1.66	156.7	+12.2
5	181.7	1.05	193.6	+11.9
6	239.0	0.96	245.6	+6.6
7	290.4	16.82	304.6	+14.2
8	311.9	1.25	316.6	+4.7
9	323.8	0.36	336.9	+13.1
10	362.0	83.82	372.4	+10.4
11	435.8	13.17	446.8	+11.0
12	458.7	1.00	466.3	+7.6
13	475.4	2.30	481.3	+5.9
14	500.2	22.21	505.0	+4.8
15	555.7	2.23	560.7	+5.0
16	558.5	19.65	575.5	+17.0
17	570.9	2.43	584.3	+13.5
18	578.9	4.96	594.4	+15.6
19	637.2	20.57	645.7	+8.5
20	644.3	66.10	678.2	+33.9
21	675.2	34.36	682.4	+7.2
22	734.9	21.65	743.5	+8.5
23	741.2	2.93	758.3	+17.1
24	760.8	30.21	779.0	+18.2
25	762.2	93.80	779.8	+17.6
26	779.0	6.23	787.4	+8.4
27	794.1	1.17	811.3	+17.2
28	844.7	3.74	862.5	+17.8
29	862.4	0.87	886.5	+24.1
30	881.1	2.53	888.5	+7.4
31	910.6	9.88	930.3	+19.7
32	929.7	0.55	953.1	+23.4
33	944.4	10.58	966.8	+22.4
34	957.3	0.24	985.1	+27.8
35	970.5	0.03	1004.2	+33.6
36	1019.5	6.20	1028.1	+8.7
37	1047.7	1.29	1056.7	+9.0
38	1111.1	44.78	1120.3	+9.2
39	1141.8	10.26	1149.4	+7.6
40	1166.7	2.88	1167.8	+1.2
41	1188.5	103.48	1183.7	-4.8
42	1193.8	362.54	1223.6	+29.8
43	1242.2	6.84	1244.3	+2.1
44	1250.8	15.41	1261.2	+10.4
45	1272.9	98.02	1282.6	+9.7
46	1311.3	4.75	1320.4	+9.1
47	1348.7	2.12	1336.5	-12.2
48	1368.4	68.74	1359.7	-8.7
49	1389.4	15.68	1371.6	-17.8
50	1394.1	166.56	1414.5	+20.4
51	1426.3	25.39	1432.1	+5.8
52	1488.2	65.05	1502.1	+13.9
53	1507.0	29.32	1519.8	+12.7
54	1537.1	1.41	1560.3	+23.2
55	1548.5	95.04	1569.6	+21.1
56	1617.9	1.83	1650.2	+32.3
57	1632.9	1.83	1664.9	+32.0
58	1666.8	3.80	1703.3	+36.5
59	1681.0	56.75	1728.2	+47.1
60	1812.0	360.42	1846.7	+34.7
61	3184.6	0.79	3227.5	+42.9
62	3191.0	2.71	3234.2	+43.2
63	3195.7	5.27	3238.3	+42.7
64	3200.9	32.10	3243.7	+42.8
65	3212.5	30.98	3254.9	+42.4
66	3221.7	1.04	3265.6	+43.9
67	3236.9	3.22	3280.3	+43.3
68	3663.9	55.50	3710.0	+46.0
69	3699.7	87.72	3740.1	+40.4

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, 2026-09-21 09:53:04 → 2026-09-21 11:13:19, 4815 s, peak 5.54 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