13509
To unravel the role of doping in iron - based superconductors , we investigated the in - plane resistivity of BaFe ( 2 ) As ( 2 ) doped at one of the three different lattice sites , Ba ( Fe ( 1 - x ) Co ( x ) ) ( 2 ) As ( 2 ) , BaFe ( 2 ) ( As ( 1 - x ) P ( x ) ) ( 2 ) , and Ba ( 1 - x ) K ( x ) Fe ( 2 ) As ( 2 ) , focusing on the doping effect in the low - temperature antiferromagnetic / orthorhombic ( AFO ) phase .
 Chemical: iron; Chemical: BaFe ( 2 ) As ( 2 ); Chemical: Ba ( Fe ( 1 - x ) Co ( x ) ) ( 2 ) As ( 2 ); Chemical: BaFe ( 2 ) ( As ( 1 - x ) P ( x ) ) ( 2 ); Chemical: Ba ( 1 - x ) K ( x ) Fe ( 2 ) As ( 2 )
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: iron; Chemical: BaFe ( 2 ) As ( 2 ); Chemical: Ba ( Fe ( 1 - x ) Co ( x ) ) ( 2 ) As ( 2 ); Chemical: BaFe ( 2 ) ( As ( 1 - x ) P ( x ) ) ( 2 ); Chemical: Ba ( 1 - x ) K ( x ) Fe ( 2 ) As ( 2 )