Assignments in the electronic spectrum of water

To explain the inelastic feature at 4.5 eV in the spectrum of water and to study its spectrum in some detail, we have carried out several calculations on the excited states of water using the equations‐of‐motion method. We conclude that the calculated vertical excitation energy of 6.9 eV for the ^3B_1 state corresponds to the strong feature at 7.2 eV observed in low‐energy electron scattering spectrum. The 4.5 eV inelastic process almost certainly does not correspond to a vertical excitation of water at the ground state geometry. The other excitation energies and oscillator strengths agree well with experiment

Developing an Internal Leadership Pipeline in Urban Districts: A Pathway to Capacity Building

The purpose of this qualitative study is to understand how an urban school district designs and implements leadership development programs for internal candidates. The challenge of continuously developing a cadre of committed and qualified leaders is not new (Darling-Hammond, LaPointe, Meyerson, Orr, & Cohen, 2007). To maintain the high standards of instructional leadership and to continue sound practices in teaching and learning, school districts must think and move strategically to protect their investments in professional development and coaching, and to secure the future growth of its students and staff. The literature is clear and consistent on the elements of effective pre-service programs, candidate selection, and program implementation (Jackson, 2001). The challenge is how to implement these elements in urban schools in an effective and sustainable way. The goal of this work is to develop effective leaders, and Marzano, McNulty, and Waters (2003) noted that at its most basic level, supporting teachers and creating effective organizational structures are key attributes of effective school leaders. Effective school leaders are at the core of teacher growth and student achievement. Without them, schools lack the vision, focus, and support they need to succeed. The population interviewed in this study was school administrators and teachers who participated in the aspiring leaders program sponsored by Paterson Public Schools in Paterson, New Jersey. In addition, central office administrators and a university partner who designed the program also participated in the study

Computational chemistry

Computational chemistry has come of age. With significant strides in computer hardware and software over the last few decades, computational chemistry has achieved full partnership with theory and experiment as a tool for understanding and predicting the behavior of a broad range of chemical, physical, and biological phenomena. The Nobel Prize award to John Pople and Walter Kohn in 1998 highlighted the importance of these advances in computational chemistry. With massively parallel computers capable of peak performance of several teraflops already on the scene and with the development of parallel software for efficient exploitation of these high-end computers, we can anticipate that computational chemistry will continue to change the scientific landscape throughout the coming century. The impact of these advances will be broad and encompassing, because chemistry is so central to the myriad of advances we anticipate in areas such as materials design, biological sciences, and chemical manufacturing

Vibrational branching ratios in photoionization of CO and N2

We report results of experimental and theoretical studies of the vibrational branching ratios for CO 4sigma(-1) photoionization from 20 to 185 eV. Comparison with results for the 2sigma(u)(-1) channel of the isoelectronic N-2 molecule shows the branching ratios for these two systems to be qualitatively different due to the underlying scattering dynamics: CO has a shape resonance at low energy but lacks a Cooper minimum at higher energies whereas the situation is reversed for N-2

Circular dichroism in photoelectron angular distributions from two‐color (1+1) REMPI of NO

A detailed experimental and theoretical study of dichroic effects in photoelectron angular distributions is reported for (1+1), two‐color REMPI of NO via the A^ 2Σ^+, v=0 state. Optically aligned A state rotational levels are probed through ionization by circularly polarized light. Resultant photoelectron angular distributions exhibit significant left–right asymmetry, the phase and magnitude of which are shown to be related to the curvature of the excited state M_J distribution. Theoretical calculations involving a full ab initio treatment of the ionization dynamics result in circularly dichroic angular distribution (CDAD) parameters in good agreement with those derived experimentally. Additional effects including hyperfine depolarization and coherence are also discussed in relation to the observed CDAD data

Photoabsorption In Carbon Monoxide: Stieltjes-tchebycheff Calculations In The Separated-channel Static-exchange Approximation

Theoretical investigations of total and partial-channel photoabsorption cross sections in carbon monoxide are reported employing the Stieltjes-Tchebycheff (S-T) technique and separated-channel static-exchange calculations. Pseudospectra of discrete transition frequencies and oscillator strengths appropriate for individual excitations of each of the six occupied molecular orbitals are constructed using Hartree-Fock core functions and normalizable Gaussian orbitals to describe the photoexcited and ejected electrons. Use of relatively large basis sets of compact and diffuse functions insures the presence of appropriate discrete Rydberg states in the calculations and provides sufficiently dense pseudospectra for the determination of convergent photoionization cross sections from the S-T technique. The calculated discrete vertical electronic excitation spectra are in very good agreement with measured band positions and intensities, and the partial-channel photoionization cross sections are in correspondingly good accord with recent electron-electron (e,2e) coincidence, synchrotron-radiation, and line-source branching-ratio measurements. Predicted resonance features in the X, B, O2s -1, and carbon K-shell channels are in particularly good agreement with the positions and intensities in the measured cross sections. A modest discrepancy between experiment and theory in the A-channel cross section is tentatively attributed to channel-coupling mechanisms associated with opening of the 1π shell. The total vertical electronic S-T photoionization cross section for parent-ion production is in excellent agreement with recent electron-ion coincidence measurements. Comparisons are made between ionization processes in carbon monoxide and in the previously studied nitrogen molecule, and similarities and differences in the respective cross sections are clarified in terms of conventional molecular-orbital theory. © 1978 American Institute of Physics.6972992300

Photoexcitation And Ionization In Ozone: Stieltjes-tchebycheff Studies In The Separated-channel Static-exchange Approximation

Theoretical studies are reported of total and partial-channel photoexcitation/ionization cross sections in ozone employing Stieltjes-Tchebycheff (S-T) techniques and the separated-channel static-exchange approximation. As in previously reported investigations of excitation and ionization spectra in diatomic and polyatomic molecules employing this approach, vertical electronic dipole transition spectra for the twelve occupied canonical Hartree-Fock symmetry orbitals in ozone are constructed using large Gaussian basis sets, appropriate computational methods, and noncentral static-exchange potentials of correct molecular symmetry. Experimental rather than Koopmans ionization potentials are employed when available in construction of transition energies to avoid the incorrect ionic-state orderings predicted by Hartree-Fock theory, and to insure that the calculated series have the appropriate limits. The spectral characteristics of the resulting improved-virtual-orbital discrete excitation series and corresponding static-exchange photoionization continua are interpreted in terms of contributions from valencelike 7a 1(σ*), 2b1(πx*), and 5b2(σ*) virtual orbitals, and appropriate diffuse Rydberg functions. The 2b1(πx*) valence orbital apparently contributes primarily to discrete or autoionizing spectra, whereas the 7a1(σ*) and 5b2(σ*) orbitals generally appear in the various photoionization continua. Moreover, there is also evidence of strong 2p→kd atomiclike contributions to ka2 final-state channels in the photoionization continua. The calculated outer-valence-shell 6a1, 4b2, and 1a2 excitation series are compared with electron impact-excitation spectra in the 9 to 13 eV interval, and the corresponding partial-channel photoionization cross sections are contrasted and compared with the results of previously reported studies of photoionization in molecular oxygen. The intermediate- and inner-valence-shell excitation series and corresponding photoionization cross sections are in general accord with quantum-defect estimates and with the measured electron-impact spectra, which are generally unstructured above ∼22 eV. Of particular interest in the intermediate-valence-shell spectra is the appearance of a strong σ→σ* feature just above threshold in the 3b2→kb2 photoionization cross section, in qualitative agreement with previously reported studies of the closely related 3σg→kσu cross section in molecular oxygen. Finally, qualitative comparisons are made of the calculated K-edge excitation and ionization spectra in ozone with recently reported photoabsorption studies in molecular oxygen. © 1981 American Institute of Physics.7484581459

Monitoring Success in Choice Neighborhoods: A Proposed Approach to Performance Measurement

Offers a framework and tools for performance management in the initiative to transform poor neighborhoods into revitalized, sustainable mixed-income communities. Proposes system components, logic model, management reports, and performance indicators

Single-photon threshold photoionization of NO

Single‐photon threshold photoionization spectra for jet‐cooled NO have been measured for the v^+=0 and 1 vibrational levels of the X ^1Σ^+ ground state of NO^+. The NO^+ rotational state distribution for the v^+=0 level is shown to be perturbed by nearby autoionizing levels, whereas the v^+=1 level exhibits a cation rotational distribution which is in near quantitative agreement with calculated spectra near threshold. Only small changes in total angular momentum are observed (‖ΔJ‖=‖J^+ − J‘‖≤5/2) even though a wide range of photoelectron angular momenta (l=0–3) are predicted to contribute to the near‐threshold photoelectron continua. The present results are also discussed in light of recently published two‐photon threshold photoionization spectra of NO which exhibit nearly identical NO^+ rotational state distributions