A new simple synthetic route to M3Se7 (M=Mo or W) core containing complexes: crystal structure and characterisation of [M3(μ3-Se)(μ-Se2)3(dtc)3]2Se

The Nature of the Chemical Bond in Linear Three-Body Systems: From I3–to Mixed Chalcogen/Halogen and Trichalcogen Moieties

“…X-ray analysis of this dication confirmed the linear geometry of the O–Se–Se moiety (165°) and an Se–Se bond (2.39 Å) which, similarly to what found in the above-described Mo and W clusters [257, 335], is only slightly elongated with respect to an Se–Se bond in diselenides (2.34 Å). This compound represents a good example of a hypervalent selenium compound having the two bonds strongly unbalanced (bond orders very far from the value of 0.5 expected for a balanced 3c-4e bond system).…”

“…This was justified by analogy with the couple I 2 /I 3 − . Linear [E–E ⋯ E] 4− systems (E= S,Se) have been found in Mo and W clusters [257, 335] containing two [M 3 ( μ 3 -E)( μ -E 2 ) 3 (dtc) 3 ] + cores (M = Mo, E = S, Se; M = W, E = Se) linked via an E 2− anion; these arrangements have been described as μ −E 2 2− dichalcogenides interacting with E 2− at significantly short distances. In the case of selenium clusters [335], the two Se–Se bonds are 2.355  Å  and 2.816  Å  for the Mo cluster and 2.38 Å  and 2.93 Å  (mean values) for the W one, the short distances being only slightly elongated with respect to the Se–Se bond length in diselenides (2.34 Å).…”

“…Linear [E–E ⋯ E] 4− systems (E= S,Se) have been found in Mo and W clusters [257, 335] containing two [M 3 ( μ 3 -E)( μ -E 2 ) 3 (dtc) 3 ] + cores (M = Mo, E = S, Se; M = W, E = Se) linked via an E 2− anion; these arrangements have been described as μ −E 2 2− dichalcogenides interacting with E 2− at significantly short distances. In the case of selenium clusters [335], the two Se–Se bonds are 2.355  Å  and 2.816  Å  for the Mo cluster and 2.38 Å  and 2.93 Å  (mean values) for the W one, the short distances being only slightly elongated with respect to the Se–Se bond length in diselenides (2.34 Å). As found for strongly asymmetric trihalides, which are better described as an X − anion interacting with an X 2 molecule (X − ⋯ X 2 ), the trichalcogen systems in which the two bonds assume very different bond orders should be better described as a chalcogen donor (in the present case E 2− ) interacting with the σ * antibonding molecular orbital of a dichalcogen species [n(E) → σ *(E–E), in the present case E 2 2 − ].…”

Crystal structure of [[Mo3Se7(S2CNEt2)3]2(μ-Se)] ⋅ 2(C6H4Cl2), C42H68Cl4Mo6N6S12Se15

“…The following procedure is a modification of the original synthesis [4]. A mixture of [Mo(CO) 6 ] (1.00 g, 3.79 mmol), Se 0 powder (1.20 g, 15.2 mmol), and Et 2 NC(S)SSC(S)NEt 2 (1.10 g, (10) 0.0309(5) Se11 0.65657(16) 0.23851(12) 0.50478 (11) 0.0480(6) Se12 0.45250(12) 0.43587(10) 0.52790 (10) 0.0273(5) Se13 0.33920(14) 0.33450(11) 0.40444 (10) 0.0378(5) Se14 0.38240(17) 0.18137(12) 0.44416 (11) 0.0512(6) Se15 0.60087(13) 0.52841(10) 0.68409 (10) 0.0316 5 3.71 mmol) was refluxed in 50 mL of 1,2-dichlorobenzene for 1.5 hours.…”

Growth of thin layers of metal sulfides by chemical vapour deposition using dual source and single source precursors: routes to Cr2S3, α-MnS and FeS

“…31 For the Cp 2 Fe experiment the product is identi®ed as a crystalline sample of FeS. 32 Thermal decomposition of Cr(S 2 CN(C 2 H 5 ) 2 ) 3 was also carried out under a nitrogen ¯ow and was monitored by Thermal Gravimetric Analysis (TGA) and Differential Thermal Analysis (DTA) as the sample was heated at a rate of 10 ³C min 21 . The TGA and DTA traces are illustrated in Fig.…”