pyridine+NO2+SH C5H4N2O2S

B_02083cff69 · SMILES O=[N+]([O-])c1ncccc1S · InChIKey VISHRKULGYMPHI-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.

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

36 vibrational modes; imaginary modes negative. Shift = ωB97X − B3LYP.

Band heights are not computed for this molecule yet (no dipole derivatives); positions only, at unit height. High wavenumbers on the left; the table below is the same data.

#	B3LYP (cm⁻¹)	ωB97X (cm⁻¹)	shift
1	47.6	118.2	+70.6
2	108.8	130.7	+21.9
3	221.3	240.3	+19.0
4	250.9	268.2	+17.2
5	291.8	309.6	+17.8
6	305.6	329.8	+24.2
7	359.0	366.2	+7.2
8	427.9	443.3	+15.4
9	450.5	463.5	+13.0
10	500.9	515.3	+14.4
11	572.0	583.2	+11.3
12	648.7	657.3	+8.6
13	709.1	731.8	+22.6
14	758.4	772.3	+13.9
15	786.3	813.3	+27.0
16	826.6	840.9	+14.4
17	869.5	888.3	+18.8
18	901.2	943.5	+42.3
19	953.5	978.6	+25.1
20	999.3	1026.1	+26.8
21	1074.0	1091.6	+17.6
22	1087.8	1103.5	+15.8
23	1162.8	1178.9	+16.1
24	1175.3	1186.3	+11.0
25	1281.4	1267.3	-14.0
26	1338.8	1326.1	-12.7
27	1388.1	1435.3	+47.3
28	1451.3	1466.5	+15.3
29	1485.0	1500.5	+15.5
30	1596.4	1633.1	+36.8
31	1633.4	1667.3	+33.9
32	1658.8	1691.6	+32.9
33	2684.3	2734.0	+49.7
34	3196.3	3238.7	+42.4
35	3204.7	3247.4	+42.7
36	3223.9	3265.9	+42.1

Structure

2D depiction from the SMILES.

Status ladder

Listed
Cheap level done — 2026-09-25, ubuntu-32gb-hel1-18
Correction predicted — not yet: the learned layer is training
Spectrum predicted — not yet: the learned layer is training
Anchored
Validated

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Second route

Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 4 cm⁻¹; wb97x max |Δω| 24 cm⁻¹.

Provenance

Releases: layerB_interim_2026-09-25
Entered the corpus as: cores with one or two substituents, enumerated from the parents (layer B)
Run: ubuntu-32gb-hel1-18, 2026-09-25 10:05:50 → 2026-09-25 10:26:00, 1210 s, peak 2.56 GB, deck 9e27bf8e9348
Imaginary modes: B3LYP 0, ωB97X 0
Source files: corpus factory · manifest