Magnetic Raman scattering of the ordered tetrahedral spin-

Raman light-scattering experiments in the antiferromagnetic phase of the $\chem{Cu_2Te_2O_5}$($\chem{Br}$$_{1-x}$$\chem{Cl}$x)2 compounds are analyzed in terms of a dimerized spin model for the tetrahedral $\chem{Cu}$-clusters. It is shown that the longitudinal magnetic excitation in the pure $\chem{Br}$ system hybridizes with a localized singlet excitation due to the presence of a Dzyaloshinskii-Moriya anisotropy term. The drastic change of the magnetic scattering intensities observed when a proportion of $\chem{Br}$ is replaced by $\chem{Cl}$ ions, is proposed to be caused by a change of the magnetic order parameter. Instead of being parallel/antiparallel with each other, the spins in the two pairs of spin-$\frac{1}{2}$ order perpendicular to each other, when the composition x is larger than about 0.25