Pairwise communication

Strictly pairwise interactions one would no longer expect any symmetry around the value 0 = 1/2 in Fig. 17, since it actually is only 0 = 1/4. A Monte Carlo study of this revised microscopic model for H on Fe(l 10) would be very interesting work on this problem is in progress (L. D. Roelefs and G. C. Gumars, private communication). 

At this point, the analogy with the static case is complete and one may take advantage of the results obtained for the static case. Interesting quantal expressions for the dynamic pair and triplet distribution functions have been communicated [297] the latter may be separated into a pairwise additive and an irreducible component, as in the static case. 

S. Chynoweth, U. C. Klomp, and L. E. Scales, Comput. Phys. Commun., 62, 297 (1991). Simulation of Organic Liquids using Pseudo-Pairwise Interatomic Forces on a Toroidal Transputer Array. 

From Table 7.1, one realizes that placing MTPs up to quadrupoles on a given site will yield nine independent parameters in spherical coordinates (i.e., one for the monopole, three for the dipole, and five for the traceless second-rank tensor). However, the main computational hurdle in MD simulations is the force calculation. Although Eq. 7.6 refers to the pairwise interaction potential, it shows that the associated force (and of course energy) will consist of n x n independent terms, where n is the number of MTP coefficients. As such, the interaction between two MTP sites, described up to quadrupole, will involve 9x9 = 81 terms—to be put in perspective with the single term prescribed by the Coulomb interaction in standard PC force fields. This certainly provides one major reason why MTP force fields have not become routine in the MD community. 

Table 5.4. Classification of pairwise interactions between microbial populations based on the signs of the entries ay, and ay from the community matrix A i — j) (May, 1973).

Metallobisfiillerene complexes are predicted to have intercage electronic communication between Cfio cages. The CV of [Rh4(CO)5(dppm)2(CNCH2C6H5)(/<3-tf-,tf-,tf--C(,(,)2] (63) exhibits six well-separated reversible, one-electron redox waves localized at ffie Cgo cages [178]. Each redox wave corresponds to sequential, pairwise addition of six electrons into ffie two Ceo centers to form eventually -Rhe-Qo - The large peak separations [( 3/2, 1/2 ) = 0-19 V,... 

Pedireddi, V. R., Jones, W., Chorlton, A. P, and Docherty, R., Creation of crystalline supramolecular assemblies using a CHLO/OHLN pairwise hydrogen bond coupling, J. Chem. Soc. Chem. Commun., 997, 1996. 

---