20869
Results by model potential calculation utilizing Li ( 2 ( 2 ) S ) instead of He * ( 2 ( 3 ) S ) for interaction between He * ( 2 ( 3 ) S ) and open - shell metallocenes do not explain the strong negative CEDPICS of the bands observed in PIES .
 Chemical: Li; Chemical: He; Chemical: He; Chemical: metallocenes
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: Li; Chemical: He; Chemical: He; Chemical: metallocenes