phenanthridine C13H9N

A_bce5bae234 · SMILES c1ccc2c(c1)cnc1ccccc12 · InChIKey RDOWQLZANAYVLL-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

46 infrared-active bands (500–3500 cm⁻¹); the strongest at 766 cm⁻¹ (13.1 µm), 79 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 — 2026-09-19, ubuntu-32gb-hel1-2
Correction predicted — not yet: the learned layer is training
Spectrum predicted — not yet: the learned layer is training
Anchored
Validated

Through the pipeline

This molecule has a recorded run: see it go through the pipeline, station by station, with its spectrum and certificate.

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)

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	98.7	0.60	108.4	+9.7
2	103.8	0.55	115.1	+11.3
3	233.6	0.00	241.5	+7.9
4	243.4	0.67	249.5	+6.1
5	250.7	0.68	261.7	+11.1
6	416.4	1.22	422.3	+5.9
7	418.9	0.33	426.7	+7.8
8	441.9	2.86	446.4	+4.5
9	454.3	2.30	458.6	+4.4
10	509.1	0.68	514.6	+5.5
11	510.4	0.77	520.1	+9.7
12	555.8	0.92	562.0	+6.3
13	559.4	0.38	563.4	+4.0
14	615.2	1.11	628.0	+12.8
15	629.6	5.69	633.2	+3.6
16	725.1	1.09	732.4	+7.4
17	735.9	6.56	746.9	+11.0
18	741.5	7.26	750.1	+8.6
19	765.7	78.78	773.3	+7.6
20	783.3	11.13	796.4	+13.2
21	810.0	0.45	819.4	+9.4
22	845.0	0.12	852.1	+7.1
23	878.1	0.04	889.5	+11.3
24	887.7	0.75	905.3	+17.6
25	901.8	12.31	912.3	+10.5
26	944.1	1.79	966.5	+22.3
27	951.5	0.00	981.2	+29.7
28	971.1	7.95	994.9	+23.8
29	991.1	0.00	1019.4	+28.3
30	993.7	0.28	1023.5	+29.8
31	1020.6	0.48	1029.0	+8.4
32	1064.2	3.89	1072.1	+8.0
33	1066.5	1.75	1074.2	+7.7
34	1129.5	0.32	1131.0	+1.5
35	1166.7	4.13	1169.6	+2.8
36	1183.7	0.94	1174.0	-9.6
37	1197.9	0.57	1197.9	+0.0
38	1227.6	2.32	1228.5	+1.0
39	1262.4	0.90	1267.3	+4.9
40	1275.4	16.81	1284.6	+9.3
41	1311.0	0.76	1313.3	+2.3
42	1330.3	0.88	1325.5	-4.8
43	1378.7	1.81	1370.3	-8.4
44	1395.1	4.48	1389.6	-5.5
45	1439.5	1.09	1446.7	+7.3
46	1454.2	1.71	1467.2	+13.0
47	1494.0	7.12	1509.0	+15.0
48	1505.1	7.28	1519.4	+14.3
49	1538.0	12.57	1559.9	+22.0
50	1581.7	7.21	1609.4	+27.7
51	1624.9	6.77	1658.9	+34.0
52	1647.6	23.67	1680.0	+32.4
53	1666.2	8.72	1707.3	+41.1
54	1674.7	8.01	1716.7	+42.0
55	3136.4	30.47	3181.9	+45.6
56	3182.0	4.73	3225.2	+43.2
57	3185.9	0.34	3229.2	+43.2
58	3190.9	14.08	3234.1	+43.3
59	3198.4	17.77	3242.1	+43.7
60	3206.3	3.84	3249.7	+43.4
61	3210.2	29.51	3253.7	+43.5
62	3218.8	32.01	3262.0	+43.2
63	3220.6	14.15	3264.7	+44.1

Second route

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

Provenance

Releases: layerA2_2026-09-23, layerA2_2026-09-23b, layerA2_2026-09-24, layerA_2026-09-22
Entered the corpus as: parent molecules chosen by hand (benzene, naphthalene, the PAH cores and their relatives) (layer A)
Run: ubuntu-32gb-hel1-2, 2026-09-19 02:59:56 → 2026-09-19 04:01:12, 3675 s, peak 4.75 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