8317
The rotational dynamics of the hexafluorophosphate anion ( PF ( 6 ) ( - ) ) in the crystalline and liquid states of the archetypal room temperature ionic liquid ( RTIL ) 1 - butyl - 3 - methylimidazolium hexafluorophosphate ( [ C ( 4 ) mim ] PF ( 6 ) ) are investigated using ( 31 ) P NMR spectroscopy line shape analyses and spin - lattice relaxation time measurements .
 Chemical: hexafluorophosphate; Chemical: PF ( 6 ) ( - ); Chemical: 1 - butyl - 3 - methylimidazolium hexafluorophosphate; Chemical: [ C ( 4 ) mim ] PF ( 6 ); Chemical: ( 31 ) P
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: hexafluorophosphate; Chemical: PF ( 6 ) ( - ); Chemical: 1 - butyl - 3 - methylimidazolium hexafluorophosphate; Chemical: [ C ( 4 ) mim ] PF ( 6 ); Chemical: ( 31 ) P