16838
Moreover , the strain energy curves of armchair imogolite - like NTs also present minima , although in all cases less stable than zigzags by at least 2 . 2 meV per atom .
 imogolite
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 imogolite