Table 2: Scaled force constants for the citric acid dimer.

DescriptionDimeraMonomerb
B3LYP/6-31G*HF/4-21G

f (ν O–H)6.616.84
f (ν C–C)3.924.34
f (ν C=O)12.0613.38
f (ν CH2)4.895.35
f (ν C–O)6.076.11
f ( 𝛿 CH2)0.750.55
f (wag CH2)1.150.65

Units in mdyn Å−1 for stretching and mdyn Å rad−2 for angle deformations.
aThis work.
bFrom [15].