27483
Structure and energetics of gas phase halogen - bonding in mono - , bi - , and tri - dentate anion receptors as studied by BIRD .
 Chemical: halogen
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: halogen 
Answer:
 Chemical: halogen