Molecular Structure, NMR, HOMO, LUMO, and Vibrational Analysis of O-Anisic Acid and Anisic Acid Based on DFT Calculations

Table 6

Diagonal force constants (10² Nm⁻¹) of O-Anisic acid (OAA) and Anisic acid (AA).

Description^a	Force constants^b
	OAA	AA
C1–C2	6.21	6.30
C2–C3	6.33	6.96
C3–C4	6.77	6.26
C4–C5	6.75	6.28
C5–C6	6.82	6.63
C6–C1	6.44	6.48
C1–C7	4.65	2.22
C7–O8	5.32	5.22
C7–O9	10.30	11.28
C2–O11(C4–O13)	4.49	5.76
O11–C12(O13–C14)	4.13	4.99
O9–H10	6.44	6.61
C12–H13(C14–H15)	4.98	5.08
C12–H14(C14–H16)	5.26	4.70
C12–H15(C14–H17)	4.98	5.07
C3–H16(C2–H11)	5.14	4.98
C4–H17(C3–H12)	5.01	4.96
C5–H18	5.05	5.00
C6–H19	5.32	5.22

aThe atoms indicated in the parenthesis belong to AA.
bStretching force constants are given in mdyn ́Å⁻¹.
For numbering of atoms refer to Figures 1(a) and 1(b).