24698
Our results also show that the HCO van der Waals complex can be formed through the interaction of CO with the H atom that is formed as a product of H2O photodissociation .
 HCO, CO, H, H2O
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 HCO, CO, H, H2O