By comparing the matrix infrared spectrum (Ar, 12. K) with theoretically ca
lculated spectra (B3LYP/6-31G*), the structure of the tube-like hydrocarbon
I has been determined to he a fast equilibrium of two D-2d symmetrical str
uctures. The previously assumed higher symmetrical D-4h structure was found
to be the transition state of this conformational interconversion. The con
formational process involves the correlated and simultaneous pincer-like mo
vement of the four relatively rigid anthracene units. Two pincers are alway
s closed and two are open. Changing the state of one of the pincers reverse
s the state of the other three pincers. Upon suitable substitution, the mol
ecular framework meets the requirements to be used as a logic gate. (C) 200
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