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Dissertation Information for Scott L. Childs

NAME:
- Scott L. Childs

DEGREE:
- Ph.D.

DISCIPLINE:
- Chemistry

SCHOOL:
- Emory University (USA) (2001)

ADVISORS:
- Karl S. Hagen

COMMITTEE MEMBERS:
- Vincent P. Conticello
- Craig L. Hill

MPACT Status: Fully Complete

Title: Nonbonded interactions in molecular crystal structures

Abstract: "Supramolecular chemistry, combined with an additional requirement of translational symmetry, is the basis of this crystal engineering study in which Kemp's Tri-acid is utilized as a molecular building block and new single crystal architectures are constructed. By co-crystallizing the same covalently bonded building block with other organic molecules, a library of structures is created that can be used to evaluate the role of non-covalent inter-molecular interactions occurring in these related structures.

KTA preferentially forms a robust one-dimensional (1D) rod motif with strong hydrogen bonds, and this rod is a thermodynamically favored motif that functions as a parent structure. In a family of host-guest structures, the 1D rod and a guest molecule self-assemble in one of two structure types depending on the point group symmetry of the guest. The robust 1D motif formed by most neutral KTA structures yields to a zero-dimensional aggregate when KTA is co-crystallized with acetic acid. Co-crystallization with nitrogen containing bases causes the cationic KTA to function as a topological director, and the resulting structures preferentially form layered motifs using charge-assisted hydrogen bonds. In addition, the C-H···O interactions involving weakly activated C-H donors with ether and carbonyl acceptors has been completed based on data retrieved from the Cambridge Structural Database.

The non-covalent interactions between molecules in crystal structures are weak compared to covalent bonds. The low energetic barriers allow for kinetically controlled systems under ambient conditions. The ability to control the shape of KTA single crystals under far from equilibrium conditions is explored by generating complex morphology. Surface recognition based on epitaxial lattice matching between two KTA co-crystals is used to create a biomimetic model system in which directed nucleation and controlled growth of assemblies of organized micro-crystals is accomplished on a single crystal substrate. Innovative and imaginative systems based on crystal engineering will continue to dissolve the boundaries between fields, with the most successful efforts remaining true to principles rooted in the fundamentals of crystallography."

MPACT Scores for Scott L. Childs

A = 0
C = 0
A+C = 0
T = 0
G = 0
W = 0
TD = 0
TA = 0
calculated 2008-04-07 08:10:49

Advisors and Advisees Graph