Structural and IR-Spectroscopic Characterization of Aqua Lithium Acesulfamate, an Outlier of the M(ace), M: Na+, K+, Rb+, Cs+, Isomorphic Series

Abstract

The crystal structure of aqua lithium 6-methyl-1,2,3,-oxathiazine-4(3H)-one, 2.2-dioxide, for short Li(ace) H 2 O, was determined by X-ray diffraction methods. It crystallizes in the triclinic P1 space group with a = 6.1750(9) Å, b = 7.3969(9) Å, c = 9.016(1) Å, α = 105.88(1)°, β = 94.59(1)°, γ = 97.80(1)°, and Z = 2 molecules per unit cell. The crystal structure of Li(ace)H 2 O sharply departs from the other heavier alkaline-metal acesulfamates, namely the monoclinic isotypic Mace (M from Na + to Cs +) family of salts. Lithium is in a distorted LiO 4 tetrahedral coordination with acesulfamate carbonyl, sulfoxide and water oxygen atoms. The FTIR spectrum of the new compound was also recorded and is briefly discussed. Some comparisons with other simple acesulfamate salts are also made.

Crystal structure of strontium and barium acesulafame (6-methyl-4-oxo-4H-1,2,3-oxathiazin-3-ide 2,2-dioxide)

“…There are over 40 acesulfame structures deposited in the Cambridge Structural Database (CSD; Groom et al, 2016;Version 5.38). Of these structures, alkali metal, ammonium, and thallium salts FEQPUP (Piro et al, 2017), KMTOZD (Paulus, 1975), SUQTOP, SURCIT and SURCOZ (Piro et al, 2015), TOFPEL (Echeverría et al, 2014), OCAHUY , magnesium salt XAGVAF (Piro et al, 2016), calcium salt EXUCOR (Demirtas et al, 2012), and protonated forms WURMOM and WURMOM01 (Velaga et al, 2010)…”