Raman spectroscopic study of centered OHO hydrogen bonding in the hydrogen maleate anion

Abstract

The work presents Raman spectra of potassium salts of the protonated K[C4H3O4] and deuterated K[C4H2DO4] maleate anion in the temperature range 5 K – 300 K. It is shown that at low (5 K) temperature roughly half of the protonated and one third of the deuterated H-bonds in maleate anions is extremely strong, the potential curve of the proton (deuteron) is single-well, in which the particles are located at the bond center, and the symmetry of the anions is C2v. As the temperature increases, the deuterons begin to shift toward one of the oxygen atoms at T > 30 K, and the proton at T > 100 K. At room temperature, the symmetry of both compounds becomes C1h.