8364
Formation and infrared absorption of protonated naphthalenes ( 1 - C10H9 + and 2 - C10H9 + ) and their neutral counterparts in solid para - hydrogen .
 Chemical: protonated naphthalenes; Chemical: 1 - C10H9 +; Chemical: 2 - C10H9 +; Chemical: para - hydrogen
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: protonated naphthalenes; Chemical: 1 - C10H9 +; Chemical: 2 - C10H9 +; Chemical: para - hydrogen