2001 年 13 巻 1 号 p. 29-36
The stacking interaction of 5, 10, 15, 20-tetramethylporphyrinatonickel (II) was calculated as a trimer by the molecular mechanics version 2 using both the point-charge model and the three-center charge model. The stacking structure for the complex was reproduced fairly well by both methods; the obtained structures are roughly in agreement with the crystal structure. By using the three-center charge model, the minimum displaced distance between each stacking molecule was consistent with the X-ray structures. On the other hand, the distance obtained from the method using the point-charge model was slightly longer. The obtained Ni—N bonds by both methods were considerably longer compared with the X-ray results. The factor for this elongation is discussed.