pyridine+CH3+F C6H6FN

B_0f29139258 · SMILES Cc1ncccc1F · InChIKey IRIHSZDBTACXCT-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	85.3	122.5	+37.2
2	169.9	181.0	+11.1
3	275.2	277.4	+2.2
4	286.8	297.7	+10.9
5	450.7	456.8	+6.0
6	457.7	470.4	+12.7
7	539.9	544.3	+4.4
8	556.4	568.7	+12.3
9	585.5	589.9	+4.4
10	734.6	749.4	+14.8
11	760.6	769.9	+9.3
12	814.3	829.8	+15.5
13	873.4	879.7	+6.3
14	938.7	957.6	+18.9
15	973.5	1001.6	+28.1
16	996.5	1002.3	+5.8
17	1070.7	1078.8	+8.1
18	1086.1	1093.3	+7.2
19	1142.3	1148.5	+6.2
20	1211.0	1210.5	-0.5
21	1287.2	1274.0	-13.2
22	1303.3	1307.6	+4.3
23	1327.0	1319.6	-7.3
24	1434.8	1444.2	+9.5
25	1489.3	1502.2	+12.9
26	1499.9	1515.5	+15.5
27	1511.3	1522.8	+11.5
28	1520.5	1532.5	+12.0
29	1631.2	1669.0	+37.8
30	1655.8	1694.0	+38.2
31	3054.4	3089.4	+35.0
32	3105.8	3155.4	+49.6
33	3163.8	3209.3	+45.6
34	3179.7	3222.8	+43.1
35	3209.0	3251.8	+42.8
36	3225.1	3267.2	+42.2

Structure

2D depiction from the SMILES.

Status ladder

Listed
Cheap level done — 2026-09-26, 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| 1 cm⁻¹; wb97x max |Δω| 16 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-hel1-18, 2026-09-26 17:04:33 → 2026-09-26 17:14:53, 619 s, peak 2.06 GB, deck 9e27bf8e9348
Imaginary modes: B3LYP 0, ωB97X 0
Source files: corpus factory · manifest