Role of phosphine ligands in gold cluster chemistry. Relativistic SCF calculations on Au2 and Au2(PH3)2

1992 ◽  
Vol 31 (2) ◽  
pp. 327-329 ◽  
Author(s):  
Peter Schwerdtfeger ◽  
Peter D. W. Boyd
2021 ◽  
Author(s):  
Aleksandra V. Paderina ◽  
Igor O Koshevoy ◽  
Elena V. Grachova

The copper subgroup metal ions in the oxidation state +1 are classical candidates for the aggregation via non-covalent metal–metal interactions, which are supported by a number of the bridging ligands....


The bonding in tertiary phosphine cluster compounds of gold is sufficiently straightforward to permit an effective interaction between theoretical concepts developed from semi-empirical molecular orbital calculations and synthetic and structural chemistry. At the simplest conceptual level the isolobal nature of the Au(PR 3 ) fragment and either the CH 3 or H radicals provides a basis for understanding the structures of a wide range of homonuclear and heteronuclear clusters, e.g. Os 3 (CO) 10 - H(AuPPh 3 ) and (OG) 5 VAu 3 (PPh 3 ) 3 . However, this simplified approach neglects some secondary gold-gold interactions between adjacent gold atoms, which arise from the availability of the higher-lying gold 6p orbitals. In low-nuclearity clusters tetrahedral fragments, which permit the effective formation of four-centre two electron bonds between the Au(PR 3 ) fragments, are preferred to larger deltahedra. In higher-nuclearity clusters the stabilities of the clusters depend on the presence of a central gold atom that provides strong radial gold-gold bonding. The relative importance of the radial and tangential components to the total bonding has been effectively demonstrated by a structural comparison of alternative Au 9 (PR 3 )3/8+ clusters. The predictive capability of the theoretical approach has been demonstrated by the synthesis and structural characterization of the icosahedral cluster [Au 13 Cl 2 (PMe 2 Ph) 10 ]3+.


2007 ◽  
Vol 62 (3) ◽  
pp. 453-459 ◽  
Author(s):  
Apollinaire Munyaneza ◽  
Muhammad D. Bala ◽  
Neil J. Coville

Reactions of (η5-RC5H4)Fe(CO)2I (R = H, Me) complexes with phosphine ligands PR′3 (R′ = Ph, m-Tol, p-C6H4OMe, p-C6H4Cl, p-C6H4F) have been performed under solvent-free conditions in the melt phase and generally yielded the ionic products [(η5-RC5H4)Fe(CO)2PR′3]I rather than the CO substituted products (η5-RC5H4)Fe(CO)(PR′3)I. The complexes have been characterised by IR, NMR and MS techniques. By contrast, the same reactions studied in benzene solution have yielded mainly the CO substitution products. Factors that affect the solvent-free reaction include variation in R and R′ , reaction temperature and the addition of [CpFe(CO)2]2 as a catalyst. The mechanism of the reaction for the formation of the ionic complex is proposed to go via a 19 electron intermediate. This is in contrast to the reaction in bezene that occurs via a 17 electron intermediate, clearly indicating the role of the melt phase in the reaction.


2019 ◽  
Vol 68 (4) ◽  
pp. 817-824
Author(s):  
N. A. Lagoda ◽  
E. V. Larina ◽  
E. V. Yarosh ◽  
A. A. Kurokhtina ◽  
A. F. Schmidt

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