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When the mixture phase is treated and included in the calculation, the coefficients of space (that is, stoichiometric numbers for the chemical potential dimensions) will be given.

1. Explanation
   
   1. The Gibbs energy of a mixture can be described in terms of the elemental chemical potentials and the elemental stoichiometric numbers as follows;
      G_mix(AxByCz) = a μ(A) + b μ(B) + c μ(C)
      Here, a, b, c, are the stoichiometric numbers of the mixture at the special elemental chemical potential values, μ(A) ... Note that temperature and pressue are neglected in this menu.
      
   2. The Gibbs energy of an ideal mixture of perovskite phases such as LaCoO3, SrCoO3, SrCoO2.5,SrCoO2 is expressed as folows;
      G_mix(LaxSryOz) = s μ(LaCoO3) + t μ(SrCoO3) + u μ(SrCoO2.5) + v μ(SrCoO2)
      
      Here, s, t, u, v are the concentration of respective constituents. Therefore, x, y, z can be written using s, t, u, v as follows;
      
      x = s
      y = t+u+v
      z = 3.0*(s+t)+2.5*U+2.0*v
      
      The sum of those constants does not necessarily become unity.
      
2. Expression
   
   • The string variable is expressed using ',' as the delimiter.
     
   • For example, A0.0B0.1C0.9 in the A-B-C- D system is described like "0.0,0.1,0.9,0.0" .
     
   • For an ideal mixture of perovskite phase such as La(1-x)SrxCoO3-d in the O-Co-La-Sr system, the expression is given as "2.88,1.0,0.8,0.2". where the first number, 2.88, is the oxygen stoichimetric num and so on.
     
   
   When the mixture does not exist as the stable phase at the point, those values are given as "0.0, 0.0, 0.0."