Coulometric titration the system LiAl

The well-defined plateau marks the equilibrium between Li-saturated aluminum and the LiAl phase. The equilibrium is described by the equation 

At higher Li concentrations a solution of A1 in Li is formed as a fourth phase. 

Measurements at Li concentrations above 60 at% Li do not hint of other LiAl phases, but the measurements at these Li concentrations are difficult and are no real proof for the non-existence of such phases. 

The evaluation of thermodynamic data follows the same principles as described in the previous chapters but the existence of intermetallic phases or compounds must be taken into account. The extrapolation to well-defined limiting values is restricted. While for solid solutions thermodynamic functions are mostly defined for a composition A Bj  

For phases of mean composition, e.g., Lig jAIq 5, another presentation of thermodynamic functions is possible. The value of a thermodynamic function relative to the value of stoichiometric composition is given. This is extensively described by Weppner et 

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