An important structural characteristic is the parameter of tetragonal lattice
distortion, which is determined as a deviation of the ratio [eta] = c/2a (a and c are unit-cell parameters) from unity .
Because of the body-centered tetragonal lattice
of S-Sn unit cell, the mechanical properties of the one-grain Sn microbumps are remarkably anisotropic, which are proved by the difference of the elastic modulus and the stiffness in the different orientations.
At ambient conditions, EuCo2As2 (14/mmm) has a tetragonal lattice
structure with a bulk modulus of 48 [+ or -] 4 GPa.
Analysis of angular position of these peeks showed their good coincidence with diffraction spectrum lines of equilibrium triple W-phase of the Al--Cu--Sc system with tetragonal lattice
of the ThMn12 type : experimental peeks of W-phase in our case correspond to values of the lattice parameters a = 0.8688 nm, c = 0.5029 nm and insignificantly differ from a = 0.855 nm, c = 0.506 nm for W-phase in the Al--Cu--Sc system with the composition [Al.sub.51.4][Cu.sub.39.7][Sc.sub.8.9] .