29199
Highly accurate calculations are reported for properties of vinylidene ( H2C = C : ) , specically the position of its zero - point vibrational level relative to that of acetylene and its equilibrium structure and ground state rotational constants .
 Chemical: vinylidene; Chemical: H2C = C :; Chemical: acetylene
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: vinylidene; Chemical: H2C = C :; Chemical: acetylene