Table 5: Calculated ground state rotational constants of trans-propenal (CH2CHCOH) with various models and basis sets.

ModelBasis set 𝐴 0 (MHz) 𝐵 0 (MHz) 𝐶 0 (MHz)

DFT
 B3LYP6-31+g(d, p)47421.3684599.2764189.265
 B3LYP6-31++g(d, 2p)47462.8334596.3044190.461
 B3LYP6-311++g(d, 2p)47713.4274621.5124213.560
 B3PW916-31g47562.8964564.8354164.742
 B3PW916-31++g(d, 2p)47445.0304617.1174207.640
 B3PW916-311++g(d, 2p)47640.4544642.9784230.737
 MPW1PW916-31g47680.5564583.5454181.241
 MPW1PW916-31++g(d, 2p)47532.1494635.3914223.524
 MPW1PW916-311++g(d, 2p)47719.8944660.6124246.017
 PBEPBE6-311g46829.5814528.5254119.901
 PBEPBE6-311++g(d, 2p)46855.3684594.9744175.330
 PBEPBE6-31++g(d, 2p)46605.7084567.8104150.825
Expt.o47353.7294659.48944242.7034

oThis work.