Home – Home – Jornals – Journal of Structural Chemistry 2012 number 2

Ab initio quantum chemical methods are employed to study the spatial and electronic structure of a 1,4-dithiine molecule. Calculations are performed with electron correlation treatment by MP2 and B3LYP methods in 6-311++G(d,p) and 6-311G basis sets. It is found that the macrocyclization of 1,4-dithiine is energetically favorable. The addition of each subsequent dithiine ring decreases the relative energy of the system by ≈0.5÷2.3 kcal/mol. The cycle consisting of 7 dithiine rings is the most comfortable from the standpoint of the internal strain of the macrocycle. With an increase in the number of rings up to 10, the macrocycle starts to break into 4-, 5-, 6-, or 7-membered fragments. The formation of a nanotube based on a 7-membered macrocycle is energetically favorable. The inner diameter of this nanotube is 6.9 Å.