13890
The decrease of the singlet exciton lifetime by charge transfer to PCBM is well described by a one - dimensional diffusion model with a P3HT domain size of approximately 5 nm for 5 - 50 wt % PCBM .
 Chemical: PCBM; Chemical: P3HT; Chemical: PCBM
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: PCBM; Chemical: P3HT; Chemical: PCBM