18653
Finally , the allowed transition dipole moments as well as the lifetimes of the five lowest vibrational states of the A ( 1 ) Pi 1 , A ' ( 1 ) Sigma ( + ) 0 ( + ) and a ( 3 ) Pi i states were obtained .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
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