The end-over-end rotational motion of nematic-phase molecules was examined by an isobaric-isothermal molecular-dynamics simulation for a Gay-Berne mesogenic system. The result was compared with the Meier-Saupe theory and the previous result obtained from a molecular-dynamics simulation for the same Gay-Berne model at constant volume in order to examine the influence of volume fluctuation on nematic-phase dynamics. The results from the simulation at constant pressure were closer to the theoretical value the retardation factor g||, which is the concept used to interpret reduction of the relaxation time for end-over-end rotational molecular motion, throughout the entire range of the second-rank orientational order parameter <P2> and the strength parameter of Maier-Saupe form σ than were those values for constant volume. Volume fluctuation is important in evaluating the retardation factor g||. This finding significantly increases our understanding of the role of pressure control in the simulation of slow dynamics in the liquid crystalline phase.
High-spin stability of non-Kekulé-type molecule triiminiummethane ion (TIM3+) is discussed using the semiempirical molecular orbital method. The triplet ground state 3A2' with a D3h geometry is predicted to lie below the Jahn-Teller distorted singlet states similar to trimethylenemethane (TMM). The lowest singlet states 1B1, 1B2 and 1A1 with C2v geometries are nearly degenerate. The spin-density distribution of the 3A2' state is calculated and the origin of the spin alignment is discussed relating to the spin-polarization rule characteristic of high-spin organic molecules. The valence bond analysis on the spin states of TIM3+ is also carried out.
In the infrared region, an expression for the mean absorption intensity has been obtained using the Elsasser model based only on the assumption of pressure broadening. Around atmospheric pressure, however, a better interpretation of the empirical results has been found by introducing a new effect of splitting due to the pressure of the degenerate vibrational-rotational levels.
Much information in today's information society goes through the Internet. On five senses smell information, DigiScent Inc. reported the development of the scent generator "iSmell" in 1999. But, it was never available and closed down in April 2001. We thought that the cause of the bankruptcy was smell blending. The smells are not blended in our policy. We developed a smell emitter which stored some element of the perfume. Ethanol and a cooling gel material were used in order to enable the emission of long term perfume. Using this device, we succeeded in transmitting/receiving the perfume mail. The result of this research indicates the future application of a smell emitter system via Internet.