pyridine+F+SH C5H4FNS

B_09903d4886 · SMILES Fc1cc(S)ccn1 · InChIKey YBQXKYLRISIJBE-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)

30 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	170.9	191.6	+20.7
2	195.3	236.8	+41.5
3	225.2	249.1	+23.9
4	237.8	267.7	+29.9
5	398.3	403.9	+5.6
6	459.1	469.0	+10.0
7	460.5	475.8	+15.3
8	567.4	571.5	+4.1
9	612.3	631.9	+19.6
10	712.6	721.1	+8.5
11	733.3	753.0	+19.6
12	830.9	843.5	+12.6
13	850.1	868.8	+18.6
14	921.7	935.0	+13.3
15	954.1	982.7	+28.6
16	977.0	1010.0	+33.0
17	1007.7	1020.7	+13.0
18	1127.1	1137.6	+10.4
19	1147.4	1154.5	+7.0
20	1280.2	1264.6	-15.6
21	1328.2	1311.1	-17.1
22	1338.5	1347.6	+9.1
23	1451.9	1467.4	+15.5
24	1519.1	1535.7	+16.5
25	1614.7	1653.0	+38.3
26	1642.3	1682.3	+40.0
27	2694.8	2739.2	+44.3
28	3187.9	3230.9	+43.0
29	3218.5	3261.4	+42.9
30	3226.8	3270.6	+43.7

Structure

2D depiction from the SMILES.

Status ladder

Listed
Cheap level done — 2026-09-27, 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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Second route

Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 2 cm⁻¹; wb97x max |Δω| 19 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, 2026-09-27 15:20:19 → 2026-09-27 15:29:48, 569 s, peak 1.9 GB, deck 9e27bf8e9348
Imaginary modes: B3LYP 0, ωB97X 0
Source files: corpus factory · manifest