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Attempts to prepare Fe(CO)5 (+) from Ag[Al(OR(F) )4 ] (R(F) =C(CF3 )3 ) and Fe(CO)5 in CH2 Cl2 yielded the first complex of a neutral metal carbonyl bound to a simple metal cation. The Ag[Fe(CO)5 ]2 (+) cation consists of two Fe(CO)5 molecules coordinating Ag(+) in an almost linear fashion. The ν(CO) modes are blue-shifted compared to Fe(CO)5 , with one band above 2143 cm(-1) indicating that back-bonding is heavily decreased in the Ag[Fe(CO)5 ]2 (+) cation.

Black AgSO4, synthesized for the first time by a displacement reaction, differs considerably from anhydrous sulfates of its Group 11 congeners: it has a very small electronic band gap (ca. 0.2 eV) and an anomalously strong one‐dimensional antiferromagnetic ordering ( J≈10 meV per Ag), which persists up to the onset of its thermal decomposition at about 120 °C. Ag gray, O red, S yellow.

A series of gold acetonitrile complexes [Au(NCMe) ] [WCA] with weakly coordinating counterions (WCAs) was synthesized by the reaction of elemental gold and nitrosyl salts [NO] [WCA] in acetonitrile ([WCA] =[GaCl ] , [B(CF ) ] , [Al(OR ) ] ; R =C(CF ) ). In the crystal structures, the [Au(NCMe) ] units appeared as monomers, dimers, or chains. A clear correlation between the aurophilicity and the coordinating ability of counterions was observed, with more strongly coordinating WCAs leading to stronger aurophilic contacts (distances, C-N stretching frequencies of [Au(NCMe) ] units). An attempt to prepare [Au(L) ] units, even with less weakly basic solvents like CH Cl , led to decomposition of the [Al(OR ) ] anion and formation of [NO(CH Cl ) ] [F(Al(OR ) ) ] . All nitrosyl reagents [NO] [WCA] were generated according to an optimized procedure and were thoroughly characterized by Raman and NMR spectroscopy. Moreover, the to date unknown species [NO] [B(CF ) CN] was prepared. Its reaction with gold unexpectedly produced [Au(NCMe) ] [Au(NCB(CF ) ) ] , in which the cyanoborate counterion acts as an anionic ligand itself. Interestingly, the auroborate anion [Au(NCB(CF ) ) ] behaves as a weakly coordinating counterion, which becomes evident from the crystallographic data and the vibrational spectral characteristics of the [Au(NCMe) ] cation in this complex. Ligand exchange in the only room temperature stable salt of this series, [Au(NCMe) ] [Al(OR ) ] , is facile and, for example, [Au(PPh )(NCMe)] [Al(OR ) ] can be selectively generated. This reactivity opens the possibility to generate various [AuL L ] [Al(OR ) ] salts through consecutive ligand-exchange reactions that offer access to a huge variety of Au complexes for gold catalysis.

Nitrous oxide is considered a poor ligand, and therefore only a handful of well-defined metal-N O complexes are known. Oxidation of copper powder with an extreme oxidant, [Ag I ][An] ([An] =[Al(OC(CF ) ) ] ) in perfluorinated hexane leads to Cu [An], the first auxiliary ligand-free Cu salt of the perfluorinated alkoxyaluminate anion. The compound is capable of forming a stable and crystalline complex with nitrous oxide, Cu(N O)[An], where the Cu-N O bond is by far the strongest among all other molecular metal-N O complexes known. Thorough characterization of the compounds together with the crystal structure of Cu(N O)[An] complex supported with DFT calculations are presented. These give insight into the bonding in the Cu -N O system and confirm N-end coordination of the ligand.

The perfluorohexane-soluble and donor-free silver compound Ag(A) (A=Al(OR(F) )4 ; R(F) =C(CF3 )3 ) prepared using a facile novel route has unprecedented capabilities to form unusual and weakly bound complexes. Here, we report on the three dihalogen-silver complexes Ag(Cl2 )A, Ag(Br2 )A, and Ag(I2 )A derived from the soluble silver compound Ag(A) (characterized by single-crystal/powder XRD, Raman spectra, and quantum-mechanical calculations).

Tiefschwarzes AgSO4 (Mr. Hyde) ist ein Halbleiter mit schmaler Bandlücke und ein extrem starkes Oxidationsmittel. W. Grochala und Mitarbeiter zeigen in ihrer Zuschrift auf dass AgSO4 in praktisch allen physikochemischen Eigenschaften von seinem leichteren Verwandten, dem unreaktiven und farblosen CuSO4 (Dr. Jekyll), abweicht. Die ungewöhnlich starke antiferromagnetische Kopplung bleibt bis zur Zersetzungstemperatur (ca. 120 °C) erhalten, wodurch es sich auch von allen anderen Übergangsmetallsulfaten unterscheidet.

] in a structure type related to that of AgF 2 . Puckered [Ag(SO 3 F) 2 ] sheets are present in the crystal structure with two oxygen atoms of the fluorosulfate anions utilized for bonding within the sheet; the third oxygen atom serves as a linker to the adjacent sheet. Terminal fluorine atoms form small cavities in the structure. The S-O stretching region of the vibrational (IR and Raman) spectra is rich in bands, thus confirming the structural complexity of Ag(SO 3 F) 2 . Ag(SO 3 F) 2 is a soft ferromagnet with a Curie temperature of 24.8 K and it shows a single broad electron spin resonance (ESR) with g = 2.183 at T = 293 K. The intrasheet magnetic superexchange constant, J, derived from