20763
This unprecedented application of such surfaces offers a paradigm shift in the emerging chemistry of Au25 research where the nanocrystals remain single and intact and where the integrity of the cluster and its solution photophysical properties are resilient in the solid state .
 Au25
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 Au25