Properties of peripheric cells in cellular structures

The metric and topological characteristics of the cells (E-cells) at the pe riphery of a sample of a cellular system are analysed. For two-dimensional (2D) systems, equations are derived for the number of E-cells per unit leng th of the boundary and for the distribution f(e) of the number e of cells a djacent to an E-cell. We obtain simple equations for the average [e], which depends on the second moment mu(2)(0) of the distribution of number of sid es of the inner cells and on the curvature of the boundary. For a straight boundary we derive the approximate relation [e](0) = 4 + mu(2)(0)/12. The r esults for 2D structures are confronted with direct measurement of the rele vant quantities in actual networks. The agreement is quite good. We also di scuss briefly E-cells in three-dimensional structures and obtain equations for the average number of neighbours of E-cells.