8011
In contrast , for strong D / A contrast systems , e . g . , thiophene ( T ) - thienopyrazine ( TP ) , the electronic properties vary nonlinearly with D / A compositions .
 Chemical: thiophene; Chemical: thienopyrazine
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: thiophene; Chemical: thienopyrazine