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Community-based participatory action research can facilitate counseling psychologists' engagement in social justice to benefit Black people's mental health. One way to improve Black mental health is to equip credible and trustworthy community members with mental health knowledge and skills to support other community members experiencing mental health challenges. This study presents the Neighborhood Healers Project—a community-based participatory action research project that trains Black adults (Neighborhood Healers Fellows) in Mental Health First Aid (MHFA). During the inaugural 12-month fellowship year, we collected longitudinal qualitative data from N = 20 Fellows on the relevance of MHFA to Black people. In this paper, we examined their responses using reflexive thematic analysis. Findings included two themes with affiliated subthemes: (a) Liberatory Paradigm Shift and (b) For Us By Us: Culturally Relevant Curriculum. We conclude with implications for counseling psychologists. [ABSTRACT FROM AUTHOR]

Localized molecular orbital energy decomposition analysis and symmetry-adapted perturbation theory (SAPT) calculations are used to analyze the two- and three-body interaction energies of four low-energy isomers of (H2O)6 in order to gain insight into the performance of several popular density functionals for describing the electrostatic, exchange-repulsion, induction, and short-range dispersion interactions between water molecules. The energy decomposition analyses indicate that all density functionals considered significantly overestimate the contributions of charge transfer to the interaction energies. Moreover, in contrast to some studies that state that density functional theory (DFT) does not include dispersion interactions, we adopt a broader definition and conclude that for (H2O)6 the short-range dispersion interactions recovered in the DFT calculations account about 75% or more of the net (short-range plus long-range) dispersion energies obtained from the SAPT calculations. [ABSTRACT FROM AUTHOR]

Adsorption structures of the dibenzo[a,j]coronene (C32H16) molecule on the clean Si(001)-2×1 surface were investigated by scanning tunneling microscopy (STM) in conjunction with electronic structure calculations. The dibenzo[a,j]coronene molecules were found to adsorb on three different sites: one major adsorption site and two minor adsorption sites. The formation of four to eight Si–C covalent bonds is responsible for the different surface bonding structures observed. Bond strain effects due to out-of-plane bending of the molecule play a significant role in governing the surface bond energies. The geometries of the three adsorption sites were established by comparison of the experimental and simulated STM images. By applying an electrical pulse, the molecule can be made to hop from one site to another site without breaking the dibenzo[a,j]coronene molecular structure. [ABSTRACT FROM AUTHOR]

The formation of negative ions in molecular beams of ethylene sulfite (ES, alternately called glycol sulfite or ethylene glycol, C2H4SO3) molecules has been studied using both Rydberg electron transfer (RET) and free electron attachment methods. RET experiments with jet-cooled ES show an unexpected broad profile of anion formation as a function of the effective quantum number (n*) of the excited rubidium atoms, with peaks at nmax*∼13.5 and 16.8. The peak at nmax*∼16.8 corresponds to an expected dipole-bound anion with an electron binding energy of 8.5 meV. It is speculated that the peak at nmax*∼13.5 derives from the formation of a distorted C2H4SO3- ion. We suggest that quasifree electron attachment promotes the breaking of one ring bond giving a long-lived acyclic anion and term this process incomplete dissociative electron attachment. Theoretical calculations of plausible ionic structures are presented and discussed. Electron beam studies of ES reveal the presence of multiple dissociative attachment channels, with the dominant fragment, SO2-, peaking at 1.3 eV and much weaker signals due to SO3-, SO-, and (ES-H)- peaking at 1.5, 1.7, and 0.9 eV, respectively. All of these products appear to originate from a broad temporary negative ion resonance centered at ∼1.4 eV. [ABSTRACT FROM AUTHOR]

The Drude model for treating the interaction of excess electrons with polar molecules is extended to calculate continuum functions and to evaluate photodetachment cross sections. The approach is applied to calculate the cross sections for photodetachment of dipole-bound electrons from HCN- and HNC-. In addition, an adiabatic model separating the angular and radial degrees of freedom of the excess electron is introduced and shown to account in a qualitative manner for the cross sections. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The parallel-tempering Monte Carlo method is used in combination with a Drude model to characterize the (H[sub 2]O)[sub 6][sup -] cluster over the 50–190 K temperature range. Chainlike structures are found to account for about 50% of the population at 190 K, whereas they are unimportant at the temperatures below about 130 K. At the lowest temperature considered, prismlike structures are dominant. Two new low-energy forms of (H[sub 2]O)[sub 6][sup -] are identified. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A one-electron model potential approach for calculating the binding energies of an excess electron interacting with water clusters is presented. Drude oscillators are employed on the water monomers to describe electron–water polarization and dispersion interactions. It is demonstrated that the resulting model gives electron binding energies very close to the predictions of ab initio CCSD(T) calculations. Dispersion interactions and high-order renormalization effects are found to make large contributions to the electron binding energies. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In order to test the reliability of plane-wave and Gaussian-orbital based DFT methods for calculating reaction energies and activation barriers, detailed calculations are performed for several reactions involving gas phase silanes and a simple model of H2 desorption from the Si(100)2×1 surface. This study is motivated in particular by apparent discrepancies between the results of cluster-model and slab-model calculations of the activation energy for H2 desorption from the Si(100)2×1 surface. The DFT results obtained with several different exchange-correlation functionals are compared with the results of calculations with the generally reliable QCISD(T) method and, where possible, with experiment. It is found that the functionals usually employed in plane-wave DFT calculations significantly underestimate the activation energies. The Becke3LYP functional, on the other hand, is found to give reaction and activation energies close to experiment and to those from QCISD(T) calculations. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Density functional theory is used in conjunction with cluster models to calculate activation energies for diffusion of H atoms on the Si(100)-2×1 surface. The activation energy for diffusion along the surface dimer rows is calculated to be 52 kcal/mol, and that for diffusion perpendicular to the dimer rows is even higher, leading us to conclude that H-atom diffusion on the Si(100)-2×1 surface probably does not play an important role in the H2 desorption process. The activation energies obtained in the present study are appreciably higher than those obtained from prior calculations using density functional theory. A major factor causing these differences is our use of the Becke3-LYP functional rather than the Becke–Perdew functional, used previously. © 1995 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Density functional theory with nonlocal corrections is used together with cluster models to examine various pathways for H2 desorption from the Si(100)2×1 surface. The barrier calculated for direct desorption of H2 from the doubly-occupied dimer is appreciably larger than the experimentally observed activation energy at submonolayer coverages. We propose a mechanism in which surface defects are converted into dihydride (SiH2) species from which H2 desorption occurs. The barrier calculated for this process (57 kcal/mol) is in excellent agreement with the measured activation energy. The barrier for defect migration is predicted to be only 14 kcal/mol, so that a single defect can account for the desorption of H2 from a large number of monohydride sites. Single-point calculations for several of the optimized structures are carried out using the quadratic configuration interaction (QCI) method. The reaction energies and barrier heights calculated with the QCI and density functional theory (DFT) methods are in excellent agreement. [ABSTRACT FROM AUTHOR]

The histogram and jump-walking algorithms are combined to deal efficiently with the problem of slow barrier crossing in Monte Carlo simulations. The utility of the histogram/jump-walking scheme is illustrated by application to the (Ar)13 and (H2O)8 clusters in their ‘‘phase transition’’ regions. Slow barrier crossing behavior is particularly acute for (H2O)8 as modeled by the TIP3P potential. Even in this case, the histogram/jump-walking algorithm proves to be quite successful at attaining equilibrium. [ABSTRACT FROM AUTHOR]

It is found that (H2O)8 possesses two nearly isoenergetic structures, one with D2d and the other with S4 symmetry, and that the (H2O)8 cluster undergoes a transition between a ‘‘solidlike’’ phase (dominated by the S4 and D2d structures) and ‘‘liquidlike’’ phase at a temperature near 119 K. [ABSTRACT FROM AUTHOR]

Both fluorescence excitation and dispersed emission techniques have been used to study the S1←S0 electronic spectra of 1- and 2-hydroxynaphthalene (1/2HN) in the collision-free environments of a supersonic jet and a twice-skimmed molecular beam, using both pulsed and high-resolution cw lasers operating in the ultraviolet. In the jet experiments, we observe that each molecule exhibits two electronic origins, separated by 274 cm-1 in 1HN and by 317 cm-1 in 2HN. In the beam experiments, we resolve the rotational structure of each of the four bands and determine the inertial constants of all eight zero-point vibrational levels, accurate to ±0.1 MHz. We also determine the orientations of the four optical transition moments in the molecular frame. Significant differences in both the inertial constants and the transition moment orientations are observed in each band. Similar experiments have been performed on the hydroxy-deuterated 1/2HN (1/2DN).A comparison of the results obtained for 1/2DN with those for the corresponding bands in 1/2HN makes possible the determination of the center-of-mass coordinates of the hydroxy hydrogen in both electronic states, accurate to ± 0.02 Å. Differences in these coordinates reveal that the two electronic origins in each spectrum are caused by the presence of two N–O–H(D) rotamers in both 1H(D)N and 2H(D)N, one with a cis (or syn) geometry and one with a trans (or anti) geometry with respect to the naphthalene frame. We make an unambiguous assignment of each origin to a specific rotamer. The lower energy origin in the spectrum of 1HN is that of the cis rotamer, whereas the lower energy origin in the spectrum of 2HN is that of the trans rotamer. We then use these results, together with those of ab initio calculations on the ground electronic states of all four isomers, to explore the reasons for the differences in their energies, to account for the orientations of their transition moments, and to... [ABSTRACT FROM AUTHOR]

The ab initio SCF-CI procedure is utilized to calculate the energies of the low-energy excitation and ionization processes in Cu and Zn, as well as the electron affinity of Cu. Although tight f functions are required for describing d2 → f2 contributions to the correlation energy of individual states, diffuse f functions are found to be generally more important for describing the differential correlation in the electronic excitation and ionization processes. [ABSTRACT FROM AUTHOR]

The configuration interaction, Möller–Plesset perturbation theory, and coupled-cluster procedures are utilized to determine the dissociation energies, vibrational frequencies, and bond lengths of CuH and Cu2. Good agreement is found between the theoretical and experimental values for these properties. Triple and quadruple excitations and the inclusion of diffuse f functions in the basis set are found to be important for quantitative predictions. A CCD+ST(CCD) approximation, in which the contributions of single and triple excitations are evaluated using the coupled-cluster doubles (CCD) wave function, is found to give a value of De(Cu2) within 0.1 eV of the experimental value when a correction for a relativistic effects is included. [ABSTRACT FROM AUTHOR]

The binding energy of the ring form of (H[SUB2]O)[SUB6] is calculated by means of the MP2 and localized-orbital MP2 (LMP2) methods. The LMP2 method is found to be effective at reducing basis set superposition error in the electron correlation contribution to the binding energy. The inclusion of f and g functions on the O atoms and d and f functions on the H atoms leads to an increase of about 3.2 kcal/mol in the stability of the ring form of (H[SUB2]O)[SUB6]. Our best estimate of the binding energy is -44.3 kcal/mol. Of this, three-body interactions contribute -11.60 kcal/mol, and the four- , five- , and six-body interactions combined contribute -2.0 kcal/mol. Although inclusion of electron correlation energy is crucial for obtaining an accurate value of the two-body interactions, the net effect of electron correlation on the three- and higher-body interactions is only about 0.2 kcal/mol. Based on these results, a computationally efficient strategy for obtaining accurate binding energies of hydrogen-bonded clusters is proposed. [ABSTRACT FROM AUTHOR]

The binding energies and configurations for single Si adatoms on the Si(100) surface are investigated theoretically. Detailed comparisons between previously published and new calculations using classical potentials, semiempirical formulations, and density functional theory (DFT) are made. The DFT calculations used both the plane-wave-pseudopotential approach in a periodic slab geometry and the Gaussian-orbital based all-electron approach employing cluster geometries. In the local-density approximation excellent agreement between the cluster and slab results was obtained. Inclusion of gradient corrections to the exchange-correlation energy significantly improves absolute binding energies and changes relative energies by as much as 0.3–0.5 eV depending on the particular exchange-correlation functional used. Binding energies and relative energies obtained using the classical potentials disagree with the gradient corrected DFT energies at about the 0.6–0.9 eV level, and most find qualitatively different local minima from those found in the DFT calculations. The semiempirical approaches give results intermediate in quality between those of the classical potentials and the ab initio calculations. Analysis of the energies and binding site geometries provides insight into the shortcomings of some of the classical potentials. © 1995 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A new variant of the stabilization method is described and used in conjunction with an analytic continuation procedure to calculate the energies and lifetimes of the lowest energy temporary anion states of N2 and Mg. With this approach excellent results are obtained for the resonance parameters even when moderate size basis sets are employed. [ABSTRACT FROM AUTHOR]

Electron transmission spectroscopy is utilized to determine the vertical electron affinities and to characterize the temporary anion states of a series of alternant hydrocarbons including benzene, naphthalene, anthracene, tetracene, styrene, and cis- and trans-stilbene. The vibrational structure present in the low lying resonances is interpreted in light of the charge distributions of the temporarily occupied orbitals. The energies of the anion states are compared with the predictions of PPP, PPP-CI, and HAM calculations, the pairing theorem and with the results from optical absorption measurements on the ground state anions in rigid glasses. [ABSTRACT FROM AUTHOR]