Encyclopedia of Crystallographic Prototypes

Al$_{2}$Ce,  Al$_{2}$Dy,  Al$_{2}$Er,  Al$_{2}$Eu,  Al$_{2}$Gd,  Al$_{2}$Ho,  Al$_{2}$La,  Al$_{2}$Lu,  Al$_{2}$Nb,  Al$_{2}$Nd,  Al$_{2}$Pr,  Al$_{2}$Pu,  Al$_{2}$Sc,  Al$_{2}$Sm,  Al$_{2}$Tb,  Al$_{2}$Tm,  Al$_{2}$U,  Al$_{2}$Y,  Al$_{2}$Yb,  Au$_{2}$Bi,  Au$_{2}$Na,  Au$_{2}$Pb,  Be$_{2}$Nb,  Be$_{2}$Ta,  Be$_{2}$Ti,  Bi$_{2}$Cs,  Bi$_{2}$K,  Bi$_{2}$Rb,  Co$_{2}$Ce,  Co$_{2}$Dy,  Co$_{2}$Er,  Co$_{2}$Gd,  Co$_{2}$Ho,  Co$_{2}$Lu,  Co$_{2}$Nb,  Co$_{2}$Nd,  Co$_{2}$Pr,  Co$_{2}$Pu,  Co$_{2}$Sc,  Co$_{2}$Sm,  Co$_{2}$Ta,  Co$_{2}$Tb,  Co$_{2}$Ti,  Co$_{2}$Tm,  Co$_{2}$U,  Co$_{2}$Y,  Co$_{2}$Yb,  Co$_{2}$Zr,  Cr$_{2}$Hf,  Cr$_{2}$Ta,  Cr$_{2}$Ti,  Cr$_{2}$Zr,  Fe$_{2}$Ce,  Fe$_{2}$Dy,  Fe$_{2}$Er,  Fe$_{2}$Gd,  Fe$_{2}$Hf,  Fe$_{2}$Ho,  Fe$_{2}$Lu,  Fe$_{2}$Pu,  Fe$_{2}$Sm,  Fe$_{2}$Tm,  Fe$_{2}$U,  Fe$_{2}$Y,  Fe$_{2}$Zr,  Hf$_{2}$Mo,  In$_{2}$Th,  Ir$_{2}$Ca,  Ir$_{2}$Ce,  Ir$_{2}$Dy,  Ir$_{2}$Er,  Ir$_{2}$Eu,  Ir$_{2}$Gd,  Ir$_{2}$Ho,  Ir$_{2}$La,  Ir$_{2}$Lu,  Ir$_{2}$Nd,  Ir$_{2}$Pr,  Ir$_{2}$Sc,  Ir$_{2}$Sr,  Ir$_{2}$Tb,  Ir$_{2}$Th,  Ir$_{2}$Tm,  Ir$_{2}$U,  Ir$_{2}$Y,  Ir$_{2}$Zr,  Mg$_{2}$Gd,  Mg$_{2}$La,  Mg$_{2}$Nd,  Mg$_{2}$Pr,  Mg$_{2}$Pu,  Mg$_{2}$Sm,  Mg$_{2}$Tb,  Mg$_{2}$Th,  Mg$_{2}$U,  Mg$_{2}$Y,  Mg$_{2}$Zr,  Mn$_{2}$Ce,  Mn$_{2}$Dy,  Mn$_{2}$Gd,  Mn$_{2}$Ho,  Mn$_{2}$Pu,  Mn$_{2}$Tb,  Mn$_{2}$U,  Mn$_{2}$Y,  Mn$_{2}$Zr,  Mo$_{2}$Zr,  Ni$_{2}$Ce,  Ni$_{2}$Dy,  Ni$_{2}$Er,  Ni$_{2}$Gd,  Ni$_{2}$Ho,  Ni$_{2}$La,  Ni$_{2}$Nd,  Ni$_{2}$Pu,  Ni$_{2}$Tm,  Os$_{2}$Ce,  Os$_{2}$La,  Os$_{2}$Pr,  Os$_{2}$Th,  Os$_{2}$U,  Pa$_{2}$Ni,  Pd$_{2}$Ba,  Pd$_{2}$Ca,  Pd$_{2}$Sr,  Pr$_{2}$Ni,  Pt$_{2}$Ba,  Pt$_{2}$Ca,  Pt$_{2}$Ce,  Pt$_{2}$Dy,  Pt$_{2}$Gd,  Pt$_{2}$Ho,  Pt$_{2}$La,  Pt$_{2}$Nd,  Pt$_{2}$Pr,  Pt$_{2}$Sm,  Pt$_{2}$Sr,  Pt$_{2}$Tb,  Pt$_{2}$Y,  Rh$_{2}$Ca,  Rh$_{2}$Ce,  Rh$_{2}$Dy,  Rh$_{2}$Er,  Rh$_{2}$Gd,  Rh$_{2}$Ho,  Rh$_{2}$La,  Rh$_{2}$Nd,  Rh$_{2}$Pr,  Rh$_{2}$Sr,  Rh$_{2}$Tb,  Rh$_{2}$Tm,  Rh$_{2}$Y,  Ru$_{2}$Ce,  Ru$_{2}$Gd,  Ru$_{2}$La,  Ru$_{2}$Nd,  Ru$_{2}$Pu,  Ru$_{2}$Sm,  Ru$_{2}$Th,  Sc$_{2}$Ni,  Sm$_{2}$Ni,  Tb$_{2}$Ni,  Th$_{2}$Ba,  Tm$_{2}$Ni,  V$_{2}$Hf,  V$_{2}$Zr,  W$_{2}$Hf,  W$_{2}$Zr,  Y$_{2}$Ni,  Yb$_{2}$Ni,  Zn$_{2}$Pu,  Zn$_{2}$Zr

\[ \begin{array}{ccc} \mathbf{a_{1}}&=&\frac{1}{2}a \,\mathbf{\hat{y}}+\frac{1}{2}a \,\mathbf{\hat{z}}\\\mathbf{a_{2}}&=&\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}a \,\mathbf{\hat{z}}\\\mathbf{a_{3}}&=&\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}a \,\mathbf{\hat{y}} \end{array}\]