phenazine C12H8N2

A_b77821c742 · SMILES c1ccc2nc3ccccc3nc2c1 · InChIKey PCNDJXKNXGMECE-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

18 infrared-active bands (500–3500 cm⁻¹); the strongest at 774 cm⁻¹ (12.9 µm), 121 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

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.

Notify me when this molecule climbs the ladder: open a GitHub issue — you are subscribed to it and we close it with a link when the page changes. No e-mail address is stored by this site.

Harmonic frequencies at the cheap level (deck v1: B3LYP and ωB97X, 6-31G*, at the B3LYP geometry)

60 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	96.8	2.64	110.1	+13.3
2	114.1	0.00	119.0	+4.9
3	244.6	0.00	249.4	+4.8
4	245.5	4.39	261.3	+15.8
5	284.8	0.00	290.7	+6.0
6	405.5	5.63	417.1	+11.6
7	418.2	0.00	419.8	+1.6
8	451.5	0.00	458.5	+7.0
9	495.9	0.36	508.1	+12.1
10	502.4	0.00	510.5	+8.1
11	508.6	0.00	521.3	+12.7
12	534.4	0.00	540.5	+6.1
13	599.2	0.00	610.0	+10.8
14	610.9	14.83	613.1	+2.3
15	624.4	0.00	629.5	+5.0
16	666.3	6.28	670.9	+4.6
17	746.8	0.00	755.5	+8.7
18	768.2	0.00	779.9	+11.7
19	773.6	121.14	783.8	+10.2
20	789.7	0.00	797.0	+7.3
21	814.6	0.00	831.0	+16.4
22	839.8	16.99	835.5	-4.3
23	885.0	0.00	898.2	+13.2
24	892.3	0.00	910.0	+17.6
25	915.3	3.51	924.5	+9.2
26	937.2	0.00	942.2	+5.0
27	976.4	1.28	1004.9	+28.5
28	978.3	0.00	1006.6	+28.3
29	1003.8	0.00	1029.5	+25.7
30	1004.0	0.00	1029.5	+25.5
31	1027.4	5.42	1035.6	+8.2
32	1030.5	0.00	1040.6	+10.0
33	1150.3	0.00	1100.2	-50.1
34	1163.3	10.15	1155.1	-8.2
35	1169.3	12.06	1170.3	+1.0
36	1187.6	0.00	1185.2	-2.4
37	1236.7	0.00	1220.6	-16.0
38	1261.4	0.00	1246.2	-15.2
39	1296.1	0.21	1304.9	+8.8
40	1321.5	0.00	1332.3	+10.7
41	1346.3	0.08	1362.3	+16.0
42	1393.2	23.73	1404.1	+10.9
43	1427.6	0.00	1434.6	+7.0
44	1441.2	0.00	1464.5	+23.3
45	1482.0	8.63	1493.0	+11.0
46	1522.8	5.60	1541.1	+18.3
47	1528.3	0.00	1550.5	+22.2
48	1572.5	32.92	1605.1	+32.6
49	1579.4	0.00	1626.9	+47.5
50	1604.6	0.00	1638.2	+33.7
51	1662.8	0.00	1700.3	+37.5
52	1691.3	2.46	1726.1	+34.8
53	3190.0	7.86	3232.6	+42.6
54	3190.1	0.00	3232.8	+42.6
55	3202.3	19.30	3245.1	+42.7
56	3202.4	2.56	3245.1	+42.7
57	3216.7	0.42	3260.0	+43.3
58	3216.9	26.17	3260.1	+43.2
59	3220.5	37.62	3263.5	+43.0
60	3221.3	4.77	3264.3	+43.0

Second route

Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 1 cm⁻¹; wb97x max |Δω| 3 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 01:31:22 → 2026-09-19 02:21:44, 3022 s, peak 4.43 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