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تسجيل مستخدم جديدStructural and magnetic properties of two branches of the Tripod Kagome Lattice family A$_{2}$RE$_{3}$Sb$_{3}$O$_{14}$ (A = Mg, Zn; RE = Pr, Nd, Gd, Tb, Dy, Ho, Er, Yb)
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We present a systematic study of the structural and magnetic properties of two branches of the rare earth Tripod Kagome Lattice (TKL) family A$_{2}$RE$_{3}$Sb$_{3}$O$_{14}$ (A = Mg, Zn; RE = Pr, Nd, Gd, Tb, Dy, Ho, Er, Yb; here, we use abbreviation textit{A-RE}, as in textit{MgPr} for Mg$_{2}$Pr$_{3}$Sb$_{3}$O$_{14}$), which complements our previously reported work on textit{MgDy}, textit{MgGd}, and textit{MgEr} cite{TKL}. The present susceptibility ($chi_{dc}$, $chi_{ac}$) and specific heat measurements reveal various magnetic ground states, including the non-magnetic singlet state for textit{MgPr}, textit{ZnPr}; long range orderings (LROs) for textit{MgGd}, textit{ZnGd}, textit{MgNd}, textit{ZnNd}, and textit{MgYb}; a long range magnetic charge ordered state for textit{MgDy}, textit{ZnDy}, and potentially for textit{MgHo}; possible spin glass states for textit{ZnEr}, textit{ZnHo}; the absence of spin ordering down to 80 mK for textit{MgEr}, textit{MgTb}, textit{ZnTb}, and textit{ZnYb} compounds. The ground states observed here bear both similarities as well as striking differences from the states found in the parent pyrochlore systems. In particular, while the TKLs display a greater tendency towards LRO, the lack of LRO in textit{MgHo}, textit{MgTb} and textit{ZnTb} can be viewed from the standpoint of a balance among spin-spin interactions, anisotropies and non-Kramers nature of single ion state. While substituting Zn for Mg changes the chemical pressure, and subtly modifies the interaction energies for compounds with larger RE ions, this substitution introduces structural disorder and modifies the ground states for compounds with smaller RE ions (Ho, Er, Yb).
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We present the structural and magnetic properties of a new compound family, Mg$_2$RE$_3$Sb$_3$O$_{14}$ (RE = Gd, Dy, Er), with a hitherto unstudied frustrating lattice, the tripod kagome structure. Susceptibility (ac, dc) and specific heat exhibit fe
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