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The geometry of cobalt( ii ) ions in the axially distorted octahedral cation in [Co(MeCN) 6 ](BF 4 ) 2 ( 1 ) was compared to the trigonal prismatic cation in [CoTp py ]PF 6 ( 2 ) which revealed significant differences in magnetic anisotropy. Combined experimental and ab initio CASSCF/NEVPT2 calculations support the observed zero field SMM behaviour for 2 , with easy axis anisotropy, attributed to the rigidity of the trigonal prismatic ligand. Strong transverse anisotropy for 1 leads to significant quantum tunnelling processes. 

The combined experimental and theoretical investigation of the magnetic properties of the cobalt( ii ) NHC complexes (NHC = N-heterocyclic carbene); [Co(CH 2 SiMe 3 ) 2 (IPr)] ( 1 ), [CoCl 2 (IMes) 2 ] ( 2 ) and [Co(CH 3 ) 2 (IMes) 2 ] ( 3 ) revealed a large easy plane anisotropy for 1 ( D = +73.7 cm −1 ) and a moderate easy axis anisotropy for 2 ( D = −7.7 cm −1 ) due to significant out-of-state spin–orbit coupling. Dynamic magnetic measurements revealed slow relaxation of the magnetization for 1 ( U eff = 22.5 K, τ 0 = 3 × 10 −7 s, 1000 Oe) and for 2 ( U eff = 20.2 K, τ 0 = 1.73 × 10 −8 s, 1500 Oe). The molecular origin of the slow relaxation phenomena was further supported by the retention of AC signal in 10% solutions in 2-MeTHF which reveals a second zero field AC signal in 1 at higher frequencies. Compound 3 was found to be an S = 1/2 system. 

A new cyclic molecule incorporating [Mo III (CN) 7 ] 4− has been characterized by single crystal X-ray methods, SQUID magnetometry and theoretical calculations. The wheel molecule [Mo III (CN) 7 ] 6 [Ni(L)] 12 (H 2 O) 6 exhibits ferromagnetic Mo–Ni coupling which did not exist for the previously reported octacyanometallate analogue [Mo IV (CN) 8 ] 6 [Ni(L)] 12 (H 2 O) 6 . These results indicate that known supramolecular architectures incorporating octacyanometallates can be used as platforms for making new molecules incorporating seven-coordinate cyanide precursors. 

Searching for a connection between the two‐electron redox behavior of Group‐14 elements and their possible use as platforms for the photoreductive elimination of chlorine, we have studied the photochemistry of [(o‐(Ph₂P)C₆H₄)₂Ge^IVCl₂]Pt^IICl₂and [(o‐(Ph₂P)C₆H₄)₂ClGe^III]Pt^IIICl₃, two newly isolated isomeric complexes. These studies show that, in the presence of a chlorine trap, both isomers convert cleanly into the platinum germyl complex [(o‐(Ph₂P)C₆H₄)₂ClGe^III]Pt^ICl with quantum yields of 1.7 % and 3.2 % for the Ge^IV–Pt^IIand Ge^III–Pt^IIIisomers, respectively. Conversion of the Ge^IV–Pt^IIisomer into the platinum germyl complex is a rare example of a light‐induced transition‐metal/main‐group‐element bond‐forming process. Finally, transient‐absorption‐spectroscopy studies carried out on the Ge^III–Pt^IIIisomer point to a ligand arene–Cl^.charge‐transfer complex as an intermediate.

 

Searching for a connection between the two‐electron redox behavior of Group‐14 elements and their possible use as platforms for the photoreductive elimination of chlorine, we have studied the photochemistry of [(o‐(Ph₂P)C₆H₄)₂Ge^IVCl₂]Pt^IICl₂and [(o‐(Ph₂P)C₆H₄)₂ClGe^III]Pt^IIICl₃, two newly isolated isomeric complexes. These studies show that, in the presence of a chlorine trap, both isomers convert cleanly into the platinum germyl complex [(o‐(Ph₂P)C₆H₄)₂ClGe^III]Pt^ICl with quantum yields of 1.7 % and 3.2 % for the Ge^IV–Pt^IIand Ge^III–Pt^IIIisomers, respectively. Conversion of the Ge^IV–Pt^IIisomer into the platinum germyl complex is a rare example of a light‐induced transition‐metal/main‐group‐element bond‐forming process. Finally, transient‐absorption‐spectroscopy studies carried out on the Ge^III–Pt^IIIisomer point to a ligand arene–Cl^.charge‐transfer complex as an intermediate.