Searching for magnetic frustration-like properties in tetrahedral spin systems Cu2Te2O5(Br1−xClx)2

The magnetic frustration in pure and substitutionally disordered compounds from the Cu2Te2O5(Br1−xClx)2 (x=1, 0.75, 0.5, 0) family of low-dimensional quantum magnets was studied experimentally by the methods of zero-field-cooled (zfc) versus field-cooled (fc) DC magnetic susceptibilities, frequency-dependent AC susceptibility and DC thermoremanent magnetization (TRM) decay. The absence of zfc-fc susceptibility splitting, frequency-independence of the AC susceptibility and zero TRM down to the temperature 2 K, that is much below the temperatures of spin ordering in these compounds, demonstrate that the spin system is different from classical magnetically frustrated systems-site-disordered spin glasses and geometrically frustrated pure antiferromagnets.