25433
Further analysis of the X - ray data , in conjunction with polarized absorption spectroscopy , suggest a lamellar packing model with alternating layers of alkyl chains and ionic dyes oriented parallel to the substrate .
 Chemical: alkyl
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: alkyl