9-methylanthracene C15H12
A_78896cfe24 · SMILES Cc1c2ccccc2cc2ccccc12 · InChIKey CPGPAVAKSZHMBP-UHFFFAOYSA-N
Cheap level done imaginary mode confirmed
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)
75 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 | -48.3 | -114.2 | -65.9 |
| 2 | 83.4 | 95.3 | +11.9 |
| 3 | 114.3 | 117.1 | +2.8 |
| 4 | 146.2 | 150.3 | +4.2 |
| 5 | 238.6 | 253.4 | +14.8 |
| 6 | 249.9 | 253.8 | +3.9 |
| 7 | 302.6 | 308.6 | +6.1 |
| 8 | 372.9 | 382.7 | +9.8 |
| 9 | 397.3 | 400.0 | +2.6 |
| 10 | 407.9 | 415.5 | +7.6 |
| 11 | 425.6 | 431.2 | +5.6 |
| 12 | 488.4 | 492.9 | +4.5 |
| 13 | 508.6 | 520.3 | +11.7 |
| 14 | 530.4 | 536.0 | +5.5 |
| 15 | 547.9 | 555.3 | +7.4 |
| 16 | 561.8 | 565.8 | +4.1 |
| 17 | 602.9 | 615.6 | +12.7 |
| 18 | 617.9 | 618.8 | +0.9 |
| 19 | 654.1 | 659.6 | +5.5 |
| 20 | 700.7 | 707.0 | +6.3 |
| 21 | 748.8 | 755.0 | +6.2 |
| 22 | 756.3 | 768.8 | +12.5 |
| 23 | 772.6 | 781.8 | +9.1 |
| 24 | 794.5 | 807.3 | +12.8 |
| 25 | 835.4 | 840.2 | +4.8 |
| 26 | 854.8 | 867.9 | +13.1 |
| 27 | 867.9 | 881.1 | +13.2 |
| 28 | 873.7 | 882.0 | +8.4 |
| 29 | 900.3 | 921.9 | +21.6 |
| 30 | 917.8 | 922.3 | +4.5 |
| 31 | 955.8 | 987.0 | +31.2 |
| 32 | 958.1 | 989.2 | +31.1 |
| 33 | 986.9 | 1015.9 | +29.0 |
| 34 | 988.1 | 1017.1 | +29.0 |
| 35 | 1033.7 | 1023.9 | -9.8 |
| 36 | 1051.2 | 1061.8 | +10.6 |
| 37 | 1055.3 | 1066.1 | +10.7 |
| 38 | 1065.6 | 1070.5 | +5.0 |
| 39 | 1091.0 | 1091.8 | +0.8 |
| 40 | 1136.4 | 1144.7 | +8.4 |
| 41 | 1185.1 | 1158.9 | -26.2 |
| 42 | 1192.4 | 1193.2 | +0.8 |
| 43 | 1212.3 | 1212.9 | +0.6 |
| 44 | 1222.9 | 1221.2 | -1.7 |
| 45 | 1263.6 | 1262.0 | -1.6 |
| 46 | 1295.4 | 1304.3 | +9.0 |
| 47 | 1316.2 | 1324.6 | +8.3 |
| 48 | 1366.5 | 1334.2 | -32.3 |
| 49 | 1382.0 | 1399.8 | +17.8 |
| 50 | 1418.1 | 1431.3 | +13.2 |
| 51 | 1430.3 | 1436.2 | +5.8 |
| 52 | 1442.9 | 1449.0 | +6.1 |
| 53 | 1453.8 | 1476.2 | +22.4 |
| 54 | 1494.8 | 1500.8 | +6.0 |
| 55 | 1495.2 | 1511.7 | +16.6 |
| 56 | 1515.9 | 1519.9 | +4.0 |
| 57 | 1528.9 | 1543.4 | +14.5 |
| 58 | 1557.4 | 1571.9 | +14.5 |
| 59 | 1582.0 | 1613.4 | +31.4 |
| 60 | 1610.5 | 1642.8 | +32.2 |
| 61 | 1634.2 | 1659.9 | +25.6 |
| 62 | 1677.6 | 1720.4 | +42.8 |
| 63 | 1686.5 | 1725.7 | +39.2 |
| 64 | 3042.6 | 3083.2 | +40.5 |
| 65 | 3120.7 | 3168.6 | +47.9 |
| 66 | 3146.6 | 3197.0 | +50.4 |
| 67 | 3173.2 | 3218.4 | +45.2 |
| 68 | 3177.8 | 3221.5 | +43.7 |
| 69 | 3180.1 | 3222.8 | +42.8 |
| 70 | 3188.4 | 3231.9 | +43.5 |
| 71 | 3188.7 | 3232.1 | +43.4 |
| 72 | 3204.6 | 3247.7 | +43.0 |
| 73 | 3205.1 | 3247.9 | +42.8 |
| 74 | 3224.1 | 3269.7 | +45.6 |
| 75 | 3225.1 | 3269.9 | +44.8 |
Second route
Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 2 cm⁻¹; wb97x max |Δω| 66 cm⁻¹.
Provenance
- Releases: none yet
- Entered the corpus as: parent molecules chosen by hand (benzene, naphthalene, the PAH cores and their relatives) (layer A)
- Run: ubuntu-32gb-hel1-2, 2026-09-18 17:27:37 → 2026-09-18 19:04:33, 5815 s, peak 6.12 GB, deck 97ed2d67c66b
- Imaginary modes: B3LYP 1, ωB97X 1
- Source files: corpus factory · manifest