Dissolving the insoluble: CdF2 and moist ammonia form cadmium(II) difluoride monohydrate—synthesis and crystal structure of [Cd(NH3)6]F2·H2O

Abstract

Hexaamminecadmium(II) fluoride monohydrate (1:1) [Cd(NH 3 ) 6 ]F 2 ÁH 2 O was synthesized from CdF 2 and liquid ammonia in open reaction vessels, so that moisture from the air was in contact with the solvent. The compound crystallizes in the chiral space group P3 1 21-D 4 3 (No. 152) in the form of needle-shaped, colorless crystals with a = 6.8974(1) Å , c = 17.7156(5) Å , V = 729.89(3) Å 3 , and Z = 3.

Fluoroferrates with (dabcoH2)2+ or (dabcoH)+ Cations

“…In III , (110) [(Fe 2 F 10 ) · 10H 2 O] sheets are described as [11$\bar{}$ 0] water ribbons linked by Fe 2 F 10 dimers (Figure 6 bottom), in which O–H ··· F and O–H ··· O bond lengths are in the range of 2.60–2.64 Å and 2.71–2.84 Å, respectively. These O–H ··· F bonds are quite strong; they are comparable to that found in the rare [F(H 2 O)F] anion of [Cu(NH 3 ) 6 ][F(H 2 O)F], 2.621 Å36 or [Cd(NH 3 ) 6 ][F(H 2 O)F] 2.614 Å 37. Inter‐layer O–H ··· N (2.85 to 2.88 Å) and N–H ··· F (2.89 to 3.18 Å) bonds ensure the stability of the 3D network.…”

The Hexaammine Copper(II) Fluoride Monohydrate [Cu(NH3)6][F(H2O)F]: Synthesis and Crystal Structure

“…The Cu-F distance is 4.018(3)Å compared to 1.9062(9) and 1.90(7)Å in pure CuF 2 [9,10]. In the isotypic Cd compound the Cd-F distance is very similar with 4.099(2)Å [7]. The fluoride anion is an acceptor of in total seven N-H•••F hydrogen bonds from four [Cu(NH 3 ) 6 ] 2+ units and from the H 2 O solvate molecule with oxygen atom O(1).…”

Zinc, cadmium and mercury

“…45 It is noteworthy that CdF 2 can now be 'dissolved' in liquid ammonia, by exposing the mixture to air at À40 1C, thus forming [Cd(NH 3 ) 6 ]F 2 .H 2 O. 46 Finally, the gas-phase reaction of group 12 MeM + with NH 3 has been investigated experimentally and theoretically, demonstrating for Zn, Cd and Hg the formation of a C-N bond, with the loss of a neutral-metal as leaving group. 47…”