Enter a species  (e.g. Al, Fe): Rb
Enter a hexagonal lattice type (e.g. hcp): hcp
Enter a model name: Morse_Shifted_GirifalcoWeizer_1959LowCutoff_Rb__MO_754498969542_003
Enter hexagonal lattice constants 'a' and 'c' (m): 5.187302425627488e-10, 8.464216256469641e-10

Calculating isothermal bulk modulus

Optimization terminated successfully.
         Current function value: -1.562696
         Iterations: 69
         Function evaluations: 184

Finished calculation

C11 = 4.076272634824028 GPa
C12 = 1.0212065637377596 GPa
  B = 2.0395619207665154 GPa