We derived explicit formulae for the eccentric connectivity index and Wiener index of 2-dimensional square-octagonal TUC4C8(R) lattices with open and closed ends. New compression factors for both indices are also computed in the limit N-->∞.

The title penta-cyclic oxindole alkadoid, isolated from Uncaria longiflora, crystallizes as a methanol solvate, C(20)H(22)N(2)O(4)·CH(4)O. The five-membered ring comprising the indole fused ring is nearly planar [maximum atomic deviation = 0.031 (2) Å], whereas the five-membered ring having alphatic C atoms adopts an envelope shape (with the tertiary N atom representing the flap). The six-membe...

The title compound, C(30)H(23)IO(2)P(2)S(2), was synthesized by the reaction of 2-iodo-benzene-1,3-diol, chloro-diphenyl-phosphine, Et(3)N and sulfur. The P=S bonds project to opposite sides of the central aromatic ring. The O-P-S and C-P-S bond angles are significantly larger than the O-P-C and C-P-C bond angles, indicating significant distortion of the tetra-hedral geometries of the P atoms. ...

The 13 non-H atoms comprising the title compound, C(9)H(10)N(2)O(2), are close to planar (r.m.s. deviation = 0.140 Å), with maximum deviations of 0.292 (1) and 0.210 (1) Å to either side of the least-squares plane exhibited by the hy-droxy and carbonyl O atoms, respectively. The observed conformation is stabilized by an intra-molecular O-H⋯N hydrogen bond. The conformation about the N=C double ...

Let G(n; m) be a connected graph without loops and multiple edges which has n vertices and m edges. We ÿnd the graphs on which the zeroth-order connectivity index, equal to the sum of degrees of vertices of G(n; m) raised to the power − 1 2 , attains maximum.

In the title compound, C(28)H(27)NP(2), the N atom adopts an almost planar geometry with the two P atoms and the C atom attached to it, with a distance of 0.066 (2) Å between the N atom and the C/P/P plane. The distorted trigonal-pyramidal geometry of the N atom is further illustrated by bond angles ranging between 115.22 (11) and 123.53 (8)°. Bond angles varying from 99.99 (9) to 108.07 (9) ° ...

The title compound, [Zn(C(7)H(4)N(2)O(3)S)(2)(C(2)H(6)OS)(2)], is a neutral four-coordinate complex with a tetra-hedral geometry. The metal atom is surrounded by the two dimethyl sulfoxide (DMSO) ligands, each coordinating through the O atom, and two anionic saccharinate (1,1,3-trioxo-2,3-dihydro-1λ(6),2-benzo-thia-zol-2-ide) ligands coordinating through the N atom. The tetra-hedral geometry is...

if $g$ is a connected graph with vertex set $v$, then the eccentric connectivity index of $g$, $xi^c(g)$, is defined as $sum_{vin v(g)}deg(v)ecc(v)$ where $deg(v)$ is the degree of a vertex $v$ and $ecc(v)$ is its eccentricity. in this paper we show some convergence in probability and an asymptotic normality based on this index in random bucket recursive trees.

The P atom in the title mol-ecule, C(12)H(26)N(3)OP, has a distorted tetra-hedral configuration: its bond angles lie in the range 101.1 (2)-119.1 (2)°. The P-N bonds to the two cyclo-pentyl-amido moieties are significantly different [1.619 (4) and 1.643 (4) Å], with the shorter bond related to an anti orientation of the lone electron pair of the corresponding N atom relative to the P=O bond. Th...

In the title compound, C(23)H(17)ClN(4)O(2), the amino H atom forms an intra-molecular hydrogen bond to the exocyclic carbonyl O atom as well as to the O atom of the benzoyl group.