Ab-initio Carbon Capture in Open-Site Metal Organic Frameworks

During the formation of metal–organic frameworks (MOFs), metal centres can coordinate with the intended organic linkers, but also with solvent molecules. In this case, subsequent activation by removal of the solvent molecules creates unsaturated ‘open’ metal sites known to have a strong affinity for CO2 molecules, but their interactions are still poorly understood. Common force fields typically underestimate by as much as two orders of magnitude the adsorption of CO2 in open-site Mg-MOF-74, which has emerged as a promising MOF for CO2 capture. Here we present a systematic procedure to generate force fields using high-level quantum chemical calculations. Monte Carlo simulations based on an ab initio force field generated for CO2 in Mg-MOF-74 shed some light on the interpretation of thermodynamic data from flue gas in this material. The force field describes accurately the chemistry of the open metal sites, and is transferable to other structures. This approach may serve in molecular simulations in general and in the study of fluid–solid interactions

The Administrator Experience with Students with Emotional and Behavioral Disorders in Comprehensive High Schools: A Phenomenological Study

This was a qualitative phenomenological study conducted in a state in the western United States. The study explored comprehensive high school administrator experiences with students with EBD with the purpose of developing a holistic description of which experiences and descriptions were shared between participants and what participants held to be the most meaningful elements of their experiences. Nine comprehensive high school administrators from seven schools, having between one and >15 years of experience as administrators and from schools serving over 1,000 students, were interviewed on this topic using a semi-structured interview format. A qualitative analytic coding process was used to analyze interview transcripts, resulting in six themes: definitions of and attitudes toward students with EBD, positive experiences, views on success, negative experiences, administrator actions and interventions, and perception of impact and relationships. An inter-rater reliability check was completed with a Cohen’s Kappa score of k= .786, indicating a high level of agreement between researchers. Agreement between administrator experiences on positive and compassionate attitude toward students with EBD, feeling ownership of these students in the school, mostly positive experiences with students with EBD, frustration with lack of adequate supports for students with EBD, and a belief that administrator impact on students with EBD primarily took place in person was found. Administrators were also found to agree on salient and meaningful elements of their experiences with students with EBD, including treating students with EBD like any other student, having clear and consistent boundaries, individualizing supports, building relationships with students with EBD, and being proactive in supporting these students. Differences in administrator experiences comprised definitions of students with EBD, views on what constitutes success for these students, in which order to address academic and behavioral needs, and the extent to which they had an impact on students with EBD and how that impact was made

The Transition of Adolescents with Emotional and Behavioral Disorders from Most-Restrictive Placements to Less-Restrictive Settings

This study examined the transition from most-restrictive to less-restrictive environments for youth with emotional and behavioral disorders (EBD). Review of the literature indicated that a transition coordinator is advised to assist the youth by coordinating between youth, family, and all agencies involved in the youth's care to develop a transition plan which should begin at intake, promoting continuity of care, self-determination, family involvement, academic and employment success, and assistance in navigating the adult mental health system. In this phenomenological study, participants were interviewed to determine the transition practices currently in place. The themes found in these interviews were: transitions differed from case to case, similarity between ideal and successful transitions, similarity in unsuccessful transitions, and barriers to transition. Transitions in practice differed from the transitions participants desired to implement, and from those transitions prescribed by the literature

Density functional theory of molecular conductivity

This thesis is about current-density functional theory. Current plays a role in three important types of physical systems: molecular electronic devices (MED), broken current-symmetry states of atoms and molecules, and states of atoms and molecules in external magnetic fields. Developments in these three areas of current-density functional theory are presented in this thesis. First, the thesis proposes an extension of conventional density functional theory that accounts for the direct current flow through a MED under a voltage bias. The irreversible current flow in a MED is introduced by coupling the MED to a pair of reservoirs at two distinct local equilibria. This coupling defines a model non-Hermitian Hamiltonian whose eigenfunctions correspond to the coherent current carrying modes of the MED. A stationarity principle for the irreversible state of MED is constructed that resembles the variational principle of conventional quantum mechanics. As an application of the stationarity principle, a generalization of Kohn-Sham density functional theory suitable for MEDs is derived. The developed current density functional theory is applied to a di-thiol benzene molecule under a voltage bias. The new approach agrees with the established non-equilibrium Green's functions method. Second, this thesis develops an approximate functional that accounts for the current dependence of the exchange-correlation energy in systems with broken current symmetry. Starting from the Perdew-Burke-Ernzerhof generalized gradient approximation, first principle conditions are employed to built a non-empirical exchange functional. Matching the correlation functional to that for exchange yields a current-dependent approximation for correlation. The resulting functional is given in a simple closed form. The benchmark of this functional against the broken current symmetry ground-states of open shell atoms indicates an improvement, as compared to the current-independent generalized gradient approximations. Third, this thesis presents a current-dependent approach to magnetic response properties of atoms and molecules. The NMR shielding tensors computed for a benchmark set of molecules indicate a superiority of the novel approach over the common generalized gradient approximations and hybrid functionals for strongly deshielded nuclei