6018
The reaction mechanism of CO oxidation on the Co ( 3 ) O ( 4 ) ( 110 ) and Co ( 3 ) O ( 4 ) ( 111 ) surfaces is investigated by means of spin - polarized density functional theory ( DFT ) within the GGA + U framework .
 Chemical: CO; Chemical: Co ( 3 ) O ( 4 ); Chemical: Co ( 3 ) O ( 4 )
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: CO; Chemical: Co ( 3 ) O ( 4 ); Chemical: Co ( 3 ) O ( 4 )