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The current study was constructed based on the recommendations of a previous study (McHenry & Borger, 2013). Though inquiry-based teaching has long been touted as an effective pedagogy, its application by middle school science teachers has been problematic. Using tools developed from the previous study in conjunction with professional development grounded in instructional coaching, the program attempted to support middle school teachers in making informed instructional decisions that enhance classroom practices to support students in reaching full science proficiency. Over the two and one-half year span of the program, researchers found that middle school teachers were able to embrace major facets of the 5E model of inquiry. While their view of the nature of science expanded slightly, they still struggle with ideas related to argumentation and theory building. The impediments that influenced the success and continuation of the program were three-fold. There was a lack of administrative partnership due to a change in upper-level district leadership. The decision to adopt new curricular materials was counter to the goals of the inquiry-based teaching model and was adopted without discussion with the university coaches. There was inadequate time allotted to the program in the last year. Though administrative difficulties led to the discontinuation of the program, the enthusiasm exhibited by the middle level teachers speaks to the need for an instructional coaching partnership that provides this type of sustained, reform-based, transformational professional development that enhances the instructional core.

Polymettalic complexes having two or more tansition-metal centers have been intensively investigated with the ultimate, increasingly successful goal to achieving unique catalytic transformations arising from cooperative reactivity effects between multiple metal centers. Multinuclear single-site catalysts and cocatalysts can be designed, which effect unusual cooperative enchainment processes and hence offered the potential of creating new macromolecular architectures.

Research has been conducted on the low-melting, volatile and fluorine-free lanthanide metal-organic chemical vapor deposition precursors. Results demonstrate the advantages of the precursors as a buffer layer for yttrium barium copper oxide films growth on these precursors.

Research has been conducted on the tris(pyrazolyl)methane complexes of sodium, potassium, calcium, and strontium. The synthesis and solid-state structures of these complexes have been investigated and the comparison of their structures to those of the lead(II) complexes has been performed.

Research has been conducted on the halogen-transfer agent tungsten hexachloride which produces tungsten oxo fragment and salicoyl chloride via the reaction with the salicylic acid. The origin of the ubiquitous oxo ligands and the reaction pathways generating these oxo products have been investigated and the results are reported.

Results indicate the solution and solid state structures of copper(I) thioether complexes are influenced by the borato ligand they contain. Complexes containing smaller (methylthio)methyl donors yield tetrameric species, while those containing larger (arylthio)methyl groups form monomeric and one-dimensional extended structures in solution and solid state, respectively.

A number of bimetallic complexes of Ni(II) and Cu-(II) of the type is isolated and characterized. The four ligands are used were bis-amines of\r bis-imines and with both di- or trimethylene links between the nonaromatic nitrogen atoms.

An ambient temperature ring-opening polymerization route to poly(thionylphosphazenes) is described.

The syntheses and molecular structures of a series of tetrahedral zinc complexes designed to model the active sites in Escherichia coli methionine synthases are described. The tridentate ligands provide the appropriate donor atoms, [S3] and [S2N], to accurately model the catalytic zinc sites in the methionine synthases from E. coli.

The structural characterization and solution thermodynamic properties of iron complexes of two of the heteropodans ligands, based on hydroxypyridinonate (HOPO) and other ligands, that are therapeutic agents for ferric ion sequestration are reported. The ligands that are described are part of a new class of heteropodate ligands, which exploit the various chelating properties of several binding units within a single tripodal ligand and allow for systematic variation of the properties for medical or other applications.

The reaction of the dihydride [Ru(super II)(H)(sub 2)(CO)(PPh3)(sub 3)] with excess azo-2,2'-bipyridine (abp) in boiling dry benzene has afforded the diradical bischelate [Ru(super II)(abp(super .-))(sub 2)(CO)(PPH3)] and the hydridic monochelate monoradical [Ru(super II)(abp(super .-))(H)(CO)(PPH3)(sub 2)]. The diradical bischelate displays strong metal-mediated antiferromagnetism, and upon oxidation to the monoradical the unpaired electron with approximately 40 percent azo pi(super star)-character gets localized in one of the chelate rings.

Short bridges prevent inside-the-cavity methylimidazole binding because of severe ligand distortions leading to high-energy penalties while long bridges flip away from the MeIm binding site allowing for penalty free MeIm inclusion. In the unbridged saddle-shaped complex, there is no energy difference between inside- and outside-the cavity MeIm binding while Molecular dynamics and free energy simulations reveal the presence of a weak noncovalent MeIm binding site at the entrance of the cleft of cobalt(II) cyclidene.

Solution NMR spectroscopy and X-ray defraction were used to synthesize and characterize mono- and binuclear Ni(super II) complexes of 26- and 32- membered macrocyclic disalen ligands. A molecular-sized cavity containing one or two embedded cofacial Ni(super II) salen sites that support host-guest chemistry were established by structural studies.

A series of novel octahedral Rh(III) salen-type complexes where the salen ligand is unsymmetrically bound to the Rh(III) dichloride center are synthesized. These complexes are the first Rh(III) salen complexes that have been isolated from the direct reaction of RhCl(sub 3)?3H(sub 2)O and the salen ligand in the absence of a nucleophilic base.

Results indicate that the O=CCO conformation is anti-periplanar in (M)-helicen-1-ol camphanates and syn-periplanar in (P)-helicen-1-ol camphanates as determined by molecular models and ROESY and X-ray diffraction methods. Data show that the lactone carbonyl faces the helicene ring system in the former and away from it in the latter.

Research has been conducted on the one-dimensional copper(I) coordination polymers. The reaction with the tridentate thioether ligand in acetonitrile is described.

Results demonstrate that lanthanide compounds bearing eta(sup)2-pyrazole ligands and neutral nitrogen donors are thermally stable to 300 C and produce highly emissive erbium-doped gallium arsenide films. Data further indicate that these compounds serve as precursors for producing films with sharp luminescence property.

Research has been conducted on the the niobium pentachloride and its reaction with cyclohexylphosphine and phenylphosphine in dichloromehtane. The isolation of the phosphonium compound is described.

A study using elemental, crystallographic structural and X-ray diffraction analyses was conducted to determine the structural and magnetic properties of trigonal bipyramid iron nitrosyl complexes. Results indicate that these iron nitrosyl complexes have almost similar molecular structures. The differences of their Fe-N-O angles have been assessed to range from 178.2(5) degrees in [Fe1iPr(NO)]- to 160.3(2) degrees in [Fe1dmp(NO)]-.

The identity of (MoOCl(detc)(H3dmp))Cl was described along with its synthesis and isolation from an alternative preparation method. In the course of the study, it was discovered that mono-oxo molybdenum dithiocarbamate complexes of reduced pterin had the ability to reduce DMSO, thus, demostrating the oxygen atom transfer reaction characteristic of molybdenum enzymes and many Mo(IV) complexes. The results from the acid/base studies showed that (MoOCl(detc)(H3dmp))Cl exists as a hydrogen bound dimer in DMSO and DMF.

The first member of a new family of tripodal thioether ligands, the methyltris((alkylthio)methyl)silanes, MeSi(CH2SR)3 R = Me, as well as its transition metal complexes, have been synthesized. The compound was prepared by reacting a pentane solution of methyltrichlorosilane with 3 equiv of LiCH2SMe. Spectroscopic data reveal that the compound is similar to tridentate crown thioethers such as 1,4,7-trithiacyclononane. The complexes are isomorphous with distorted octahedral structures and face-capping tridentate thioether ligands.

The synthesis of the complex ((4,4'-Me2bipy)Li(mu-eta3-BH4))2 with bipy = bipyridyl and a series of lithium borohydride complexes made from (pyrazolyl)methane ligands have been undertaken. The solid structures of (HC-(3,5-Me2pz)3)Li(eta3-BH4) and ((H2C(3,5-Me2pz)2)Li(mu-eta3-BH4))2 have also been studied. The resulting coordination compounds are more stable in air than LiBH4.

New homoscorpionate ligands hydrotris(3-cyclopropylpyrazol-1-yl)borate, TpCpr, and tetrakis(3-cyclopropylpyrazol-1-yl)borate, pz*TpCpr have been derived. They form octahedral homoleptic and heteroleptic complexes with first-row transition metal compounds but their (M(TpCpr)(X)) complexes are unstable relative to the octahedral complexes. TpCpr is similar to TpMe but different to TpiPr in its coordination chemistry.

Homoleptic, d0 early transition metal acetylide derivatives were synthesized using the extremely bulky tBu3SiC equivalent to C- ligand. The SitBu3 group was utilized to circumvent synthetic difficulties in preparing the derivatives. Structural characterizations showed a distorted trigonal prismatic configuration for (tBu3SiC equivalent to C)6Ta(super -) and an octahedral geometry for (tBu3SiC equivalent to C)6M(super 2-) (M = Zr, Hf). The distortion in the case of tantalum was caused by steric interactions of the tBu3Si groups.

The size of the alkali metal cation and the donor solvents used for crystallization determine the structural motif found in molecular species of heavier congeners of alkali metal phosphides. This was gleaned from a study of the structural aspects of several systems of heavier alkali metal congeners of supermesitylphosphane with regard to structural changes that are produced from alkali metal cation/solvent combinations used in the crystallization process. The molecular structural determinations of a number of different rubidium and cesium derivatives of supermesitylphosphane are reported.

A study was conducted on the coordination chemistry of titanium tetrachloride with dialkyl diselenides and the resultant complexes as single-source precursors of TiSe2 films. The findings indicate that titanium diselenide films prepared from TiCl4(Se(CH2CH3)2)2 are sensitive to moisture and are hydrolyzed by ambient moisture to titanium dioxide and hydrogen selenide.

A new synthetic route to metallo-1,2-enedithiolates was applied to the synthesis of (dppe)M(Ssub2Csub2-(R)(R')); M = Ni, Pd, and Pt, and R(R') = 2-, 3- and 4-pyridine (H), 2-pyrazine (H) and 2-quinoxaline (H or Me). The heterocyclic substituted 1,2-enedithiolate compounds seved as a luminescent chromophore, and were more basic than a free heterocycle.

The 2,3-disulfidothienoquinoxaline complexes of Cp2-Mo and dppePd and the 2,3-disulfidothienopyridine complexes of Cp2Mo were characterized as S8 oxidation states of their correspoding metallo-1,2-enedithiolates. The S8 oxidation products such as 2-sulfido-3-oxidothienoquinoxaline complexes of Cp2Ti, Cp2Mo, dppePd and dppePt were also synthesized from 1-(quinoxalin-2-yl)-2-bromoethanone and their corresponding polysulfido complex. Furthermore, the resulting compounds exhibited extended planr ring configurations with metal centers that were bonded with the thiophene ring.

The oxidation of an iron(II)-vanadium(III) system with an oxo transfer reagent was investigated to demonstrate the independence of this mutual oxidation from metals. Three monometallic complexes exhibited more positive potentials as compared to complexes with an en link. Conformational flexibility of the ligand had a strong influence on the redox potential. The large positive potential possessed by the open-site iron(II) in the bimetallic complex indicated the presence of special forms of deactivation in the complexes.

Nuclear magnetic resonance spectroscopy, X-ray crystallography, voltammetry and extended Huckel studies were done to define the electrochemical and structural properties of a series of synthetic mononuclear rhodium(II) bis(phosphine), eta-6-arene complexes. The complexes, collectively called piano-stool compounds, were found to acquire their stability based on the following factors: the arene substituents, the presence or absence of ligand chelation, the type of ligand chelation and the structural changes which may occur on oxidation of the metal center.

The derivative Sn6(mu3-O)4(mu3-OSiMe3)4 was synthesized via a high-yielding procedure involving the solvent-free thermolysis of bis(bis(trimethylsilanolato)tin) and characterized with respect to its reaction with Fe2(CO)9. The results, which were (Fe(CO)4) Sn6(mu3-O)4(mu3-OSiMe3)4 and (Fe(CO)4)2Sn6(mu3-O)4(mu3-OSiMe3)4, underscored the compound's use in the formation of mixed p-d metal complexes through the activity of its tin(II) center as 2e sigma-donors.

A series of redox-switchable hemilabile ligands (RHLs) that incorporate ferrocene as the redox group and phosphine ether or phosphine thioether molecules as binding groups was synthesized. Electrostatic effects were observed to play an essential role in the charge dependent behaviors of these complexes. Also, there is a correlation between the phosphine substituents and RHL-complex stability.

Mesitylphosphines were utilized for the displacemement of weakly coordinating cyclooctadiene, acetonitrile and tetrafluoroborate ligands during the synthesis of NiL4, [PdL4][BF4]2, [CuL4]PF6 and [AgL4]BF4. The rate of ligand dissociation of the mesitylphosphine complexes was hindered by the small cone angle of L. Furthermore, structural analysis of the complex indicated the presence of N-L pi-back-bonding interactions.

A general method for synthesizing silole and germole derivatives, based on Fagan's zirconocene-mediated route to the dihalides C4Me4GeCl2 and C4Me4SiBr2 is presented. This approach offers a convenient synthetic pathway to silolyl and germolyl anions, and silole and germole dianions. The siloyl anions showed coalescence temperatures below the freezing point of tetrahydrofuran (165 K), but upper limits to the inversion barriers were estimated from spectra recorded at the lowest temperatures.

The syntheses of cadmium(II) complexes in nonaqueous solutions is achieved from the prepared (Cd2 thf 5)(BF4)4, where thf = tetrahydrofuran. The complex reacts with HC(3,5-Me2pz)3 or HC(3-Phpz)3 to produce dicationic, homoleptic compounds ( HC 3,5-Me2pz 3 2Cd) (BH4)2 and ( HC 3-Phpz 3 2Cd)(BF4)2 where pz = pyrazolyl. The former has a cationic structure which is similar with that of (HB 3,5-Me2pz 3)2Cd and only deviating in the Cd-N bond distances by 0.03 angstrom. The 113Cd chemical shifts of complexes having similarly substituted pyrazolyl rings are closely similar regardless of the charges.

The nucleophilic substitution of cyclic thionylphosphazenes, (NSOX(NPCl2)2), with phenoxide, trifluoroethoxide, and butoxide is regioselective at the phosphorus centers. The 31P- and 19F-NMR spectra show the formation of a single isomer of mono-, di- and tri-substituted cyclothionylphosphazene. The substitution occurs through a vicinal pathway. In a substitutional control of the reaction using phenoxide and butoxide as nucleophiles, the order of reactivity is PCl2 > PCl(OR) > SOX where X = Cl, F.

The syntheses and characterization of Pd(II) and Pt(II) chloride complexes primary arylphosphines are presented. The primary phosphido-bridged dimer (Pt PH2Mes mu-PHMes Cl)2, where Mes = 2,4,6-Me3C6H2, was formed from the spontaneous dehydrochlorination of cis-Pt(PH2Mes)Cl2. Reactions of the product with phosphines result in displacement of chloride as an ion and substitution of the terminal PH2Mes ligand to form a series of mu-phosphido dimers.

Two new homoscorpionates, Tp(super Me,mt3) and Tp(super Me,Mt4) were prepared, as the first examples of Tp(super x) ligands containing a 3-Me but 5R-substituents other than Me. X-ray crystallography was used to determine the structures of Co[Tp(super Me,mt3)][Tp(super Nt)] and Rh[Tp(super Me,mt4)](COD).

Research has been conducted on the scorpionate ligand synthesis. The first oxygen-based example of expanded denticity is discussed.

Research was conducted to examine the solid state structure of ((HC(3,5-Me2pz)3)(HB(3,5-Me2pz)3)Cd)(B(3,5-(CF3)2C6H3)4) that permits a direct comparison of the two ligand types in the same complex. A comparison to the previously reported structures of ((HC(3,5-Me2pz)3)2Cd)(BF4)2(super 4) and ((HB(3,5-Me2pz)3)2Cd) with the structures of the analogous lead(II) complexes ((HC(3,5-Me2pz)3)2Pb)2+ 5, (HB(3,5-Me2pz)3)2Pb6 and ((HC(3,5-Me2pz)3)(HB(3,5-Me2pz)3)Pb)+5 was performed.

A combination of X-ray diffraction, NMR and IR spectroscopy, and DFT calculations are used to study the hydrogen bonding phenomena for the series of complexes of the form Cp*Ir([L.sub.1])([L.sub.2])(phosphine). The obtained results highlighted the difficulty of characterizing hemilabile, bifunctional complexes and the importance of innocent ligand substituents in determining structure and dynamics.