New mixed salts of L-histidinium(2+) comprising hexafluorosilicate anion.

Four mixed salts of amino acid L-histidine comprising hexafluorosilicate anion have been obtained in form of single crystals. These mixed salts are: orthorhombic 2L-His2+⋅2ClO4-⋅SiF62-⋅2H2O (space group P21212, Z=2, a=10.1549(8) Å, b=14.847(1) Å, c=8.7536(7) Å, which is isostructural with recently published 2L-His2+⋅2BF4-⋅SiF62-⋅2H2O), monoclinic 2L-His2+⋅2Cl-⋅SiF62- (space group C2, Z=2, a=27.037(2) Å, b=6.9849(5) Å, c=5.3630(4) Å, β=91.928(4)°) and isostructural 2L-His2+⋅2Br-⋅SiF62- (space group C2, Z=2, a=27.063(6) Å, b=7.1013(17) Å, c=5.5076(11) Å, β=92.141(11)°), and triclinic 2L-His2+⋅SO42-⋅SiF62-⋅3H2O (space group P1, Z=1, a=8.5005(17) Å, b=8.7896(18) Å, c=9.7286(19) Å, α=71.49(3)°, β=92.141(11)°, γ=86.17(3)°). [ABSTRACT FROM AUTHOR]