Yttrium atoms, reactions

Fig. 9. Time-of-flight spectra for non-reactively scattered yttrium atoms at indicated lab angles for the Y + CH3OH reaction at Eco = 28.1 kcal/mol. Fits data generated using the CM distributions shown in Fig. 10.

A mixed metal siloxide complex YCu(OSiPh3)4(PMe2Ph) was obtained by a simple addition reaction (Eq. 3) [48], The geometry around the yttrium atom is distorted tetrahedral. The molecule is cleaved in solution by Lewis basic solvents like THF. 

The generation of reactive species by a fast pre-reaction is a well established process in kinetics, particularly in flow systems, although this technique is now being used in molecular beam sources [see (f), below]. As atoms are commonly generated by thermal or microwave dissociation (see above), reactions are mainly used to produce radicals. However, some atoms may be produced by reaction as a more convenient alternative to direct vaporisation or dissociation. Scandium and yttrium atoms have been generated [25] by the reaction... 

Interest in barium yttrium alkoxides stems from metal organic vapor deposition experiments for the preparation of superconducting thin films. The compound [Y4Ba20(0Et)8(dmp)6] (where dmp = B C CHC Bu1) has been prepared by the reaction of Y50(0Pr1)13 with Ba(OEt)2 (PPOH) in the presence of dmpH.167 The structure contains seven-coordinate yttrium atoms with... 

A similar approach can be applied for the Y atom insertion into the C-H bond of alkenes and other alkanes. Our calculation by the Cl method in a 6-311-H-G(2d,2p) basis set with a complete active space for 8 electrons in 8 orbitals (Is orbital of carbon atom is frozen) predicts that the vertical S-T excitation energy in methane is around 11 eV (11.37 eV or 262 kcal/mol). Following the above approximation it is equal -2 Jch- From Eq. (9) the activation energy for the yttrium atom insertion reaction, Eq. (1) M=Y, should be 17.6 kcal/mol. This simple estimation is in a good agreement with very accurate ab initio calculations, Ea = 20.7 kcal/mol [15]. 

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