28963
The lateral organization of the hydrocarbon lipid chains displays an oblique hexagonal unit cell at all surface pressures , with only the chain tilt angle changing with surface pressure .
 Chemical: hydrocarbon
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: hydrocarbon