18933
We report an approach based on a combination of inductively coupled plasma mass spectrometry and X - ray photoelectron spectroscopy for quantitative analysis of the role played by Br ( - ) ions in the synthesis of Pd nanocrystals .
 Br ( - ), Pd
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 Br ( - ), Pd