Zusammenfassung
We report the first solvate structure of the silicide anion Si-4(4-), which provides circumstantial evidence of the stability of the highly charged anion in liquid ammonia solutions. The solvate Rb(1.2)K(2.8)Si(4)7NH(3) crystallized from a mixture of the ternary compound K6Rb6Si17 with the transition metal complex [(C6H5)(3)P](2)Ni(CO)(2) [bis(triphenylphosphine)dicarbonylnickel] in the presence ...
Zusammenfassung
We report the first solvate structure of the silicide anion Si-4(4-), which provides circumstantial evidence of the stability of the highly charged anion in liquid ammonia solutions. The solvate Rb(1.2)K(2.8)Si(4)7NH(3) crystallized from a mixture of the ternary compound K6Rb6Si17 with the transition metal complex [(C6H5)(3)P](2)Ni(CO)(2) [bis(triphenylphosphine)dicarbonylnickel] in the presence of the chelating agents 18-crown-6 (1,4,7,10,13,16-hexaoxacyclooctadecane) and [2.2.2]cryptand (4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane) in liquid ammonia. Single X-ray diffraction analysis confirms the presence of the Si-4(4-) anion in the crystal structure of Rb(1.2)K(2.8)Si(4)7NH(3), which represents the first solvate compound of the naked tetrasilicide tetraanion. All five crystallographically independent cation positions show mixed occupancy by Rb+ and K+.