13465
IR , NMR , and potentiometric analysis revealed that both Zn ( 2 + ) and Cd ( 2 + ) are coordinated with two pyridine N , amine N , and amide O ; however , the Zn ( 2 + ) center is also coordinated with a hydroxide anion ( OH ( - ) ) .
 Zn ( 2 + ), Cd ( 2 + ), pyridine, N, amine, N, amide, O, Zn ( 2 + ), hydroxide, OH ( - )
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 Zn ( 2 + ), Cd ( 2 + ), pyridine, N, amine, N, amide, O, Zn ( 2 + ), hydroxide, OH ( - )