1from ase.data import atomic_numbers, reference_states, chemical_symbols 2 3 4def get_element_info(symbol, latticeconstant): 5 if isinstance(symbol, str): 6 atomic_number = atomic_numbers[symbol] 7 else: 8 atomic_number = symbol 9 symbol = chemical_symbols[atomic_number] 10 11 if latticeconstant is None: 12 if reference_states[atomic_number]['symmetry'] in ['fcc', 'bcc', 'sc']: 13 lattice_constant = reference_states[atomic_number]['a'] 14 else: 15 raise NotImplementedError( 16 ("Cannot guess lattice constant of a %s element." % 17 (reference_states[atomic_number]['symmetry'],))) 18 else: 19 if isinstance(latticeconstant, (int, float)): 20 lattice_constant = latticeconstant 21 else: 22 raise ValueError("Lattice constant must be of type int or float.") 23 24 return symbol, atomic_number, lattice_constant 25