The synthesis and structural characterization of novel transition metal fluorides
High purity KMF[sub 6] and K[sub 2]MF[sub 6] salts (M = Mo, Re, Ru, Os, Ir, Pt) are obtained from reduction of the hexafluorides. Fluoride ion capture by Lewis acids from the hexafluorometallate (IV) salts affords high purity tetrafluorides for M = Mo, Re, Ru, Os, and Pd. The structure of RuF[sub 4] is determined from a combination of X-ray synchrotron and neutron powder data. The structure is related to the layered SnF[sub 4] type, however, a puckering of the sheets occurs in the monoclinic RuF[sub 4] unit cell. Unit cells based on the orthorhombic PdF[sub 4] type cell are derived from X-ray powder data for ReF[sub 4]. Fluoride ion capture from KAgF[sub 4] provides the thermally unstable trifluoride as a bright, red, diamagnetic solid. The structure solution of AgF[sub 3] and the redetermination of the AuF[sub 3] structure from X-ray synchrotron and neutron powder data demonstrate that the two are isostructural. The thermal decomposition product of AgF[sub 3] is the mixed valence compound Ag[sup II]Ag[sup III][sub 2]F[sub 8]. Several new salts containing the (Ag-F)[sup n+][sub n] chain cation are prepared. The first linear (Ag-F)[sup n+][sub n] chain is observed in AgF[sup +]BF[sub 4] - which crystallizes in a tetragonal unit cell and is isostructural with CuFAuF[sub 4]. AgFAuF[sub 6] has an orthorhombic unit cell and appears to be isostructural with AgFAsF[sub 6]. A second mixed valence silver fluoride, Ag[sup II]Ag[sup III]F[sub 5], is prepared, which magnetic measurements indicate is probably an AgF[sup +] salt. Magnetic data for all of the AgF[sup +] salts exhibit low magnitude, temperature independent paramagnetism characteristic of metallic systems. Cationic Ag(II) in acidic AHF solutions is demonstrated to be an exceedingly powerful oxidizer, capable of oxidizing Xe to Xe(II) and O[sub 2] to O[sup +][sub 2]. Reactions with C[sub 6]F[sub 6] and C[sub 3]F[sub 6] suggest an electron capture mechanism for cationic Ag(II) oxidations.
- Research Organization:
- California Univ., Berkeley, CA (United States)
- OSTI ID:
- 6889407
- Country of Publication:
- United States
- Language:
- English
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The synthesis and structural characterization of novel transition metal fluorides
Disproportionation of Ag(II) to Ag(I) and Ag(III) in fluoride systems and syntheses and structures of (AgF{sup +}){sub 2}AgF{sub 4}{sup {minus}}MF{sub 6}{sup {minus}} salts (M = As, Sb, Pt, Au, Ru)
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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201 -- Chemical & Physicochemical Properties
ALKALI METAL COMPOUNDS
ALLOYS
CHEMICAL PREPARATION
CHEMICAL PROPERTIES
CRYSTAL STRUCTURE
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
INTERMETALLIC COMPOUNDS
LATTICE PARAMETERS
POTASSIUM COMPOUNDS
POTASSIUM FLUORIDES
SYNTHESIS
TRANSITION ELEMENT COMPOUNDS