Experimental and computational studies of the structure and vibrational spectra of pyridinium-betaine of squaric acid.
The FTIR spectra of pyridinium-betaine of squaric acid in 4000-100 cm(-1) frequency region in solid state were measured. In addition, the structure and harmonic vibrational frequencies of this molecule were theoretically evaluated using restricted Hartree-Fock and B3LYP density functional methods. The computed vibrational frequencies are used to determine the types of molecular motions associated with each of the experimental bands observed. Comparison with the experimental spectra provides important information about the ability of these computational methods to describe the vibrational modes in these highly polar strained ring compounds.
Institute of Organic Chemistry, Bulgarian Academy of Sciences, Bulding 9, Bonchev str, 1113 Sofia, Bulgaria. kolev@orgchm.bas.bg
Tsonko M
TM
Kolev
Denitsa Y
DY
Yancheva
Bistra A
BA
Stamboliyska
D001622:Betaine / Q000737:chemistry*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003503:Cyclobutanes / Q000737:chemistry*; D004583:Electrons; D008956:Models, Chemical; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*
D003503:Cyclobutanes; D001622:Betaine; C030042:squaric acid