73 research outputs found
Computation of conical intersections by using perturbation techniques
Multiconfigurational second-order perturbation theory, both in its single-state multiconfigurational second-order perturbation theory (CASPT2) and multistate (MS-CASPT2) formulations, is used to search for minima on the crossing seams between different potential energy hypersurfaces of electronic states in several molecular systems. The performance of the procedures is tested and discussed, focusing on the problem of the nonorthogonality of the single-state perturbative solutions. In different cases the obtained structures and energy differences are compared with available complete active space self-consistent field and multireference configuration interaction solutions. Calculations on different state crossings in LiF, formaldehyde, the ethene dimer, and the penta-2,4-dieniminium cation illustrate the discussions. Practical procedures to validate the CASPT2 solutions in polyatomic systems are explored, while it is shown that the application of the MS-CASPT2 procedure is not straightforward and requires a careful analysis of the stability of the results with the quality of the reference wave functions, that is, the size of the active [email protected]
[email protected]
[email protected]
CASSCF calculations for photoinduced processes in large molecules: Choosing when to use the RASSCF, ONIOM and MMVB approximations
Can the computer replace the adult for storybook reading? A meta-analysis on the effects of multimedia stories as compared to sharing print stories with an adult
The present meta-analysis challenges the notion that young children necessarily need adult scaffolding in order to understand a narrative story and learn words as long as they encounter optimally designed multimedia stories. Including 29 studies and 1272 children, multimedia stories were found more beneficial than encounters with traditional story materials that did not include the help of an adult for story comprehension (g+ = 0.40, k = 18) as well as vocabulary (g+ = 0.30, k = 11). However, no significant differences were found between the learning outcomes of multimedia stories and sharing traditional print-like stories with an adult. It is concluded that multimedia features like animated illustrations, background music and sound effects provide similar scaffolding of story comprehension and word learning as an adult
Systematic Fragmentation Method and the Effective Fragment Potential: An Efficient Method for Capturing Molecular Energies
Results of variable grass seeding rates on community development in a sand prairie restoration experiment in the Manistee National Forest, Michigan
Sand prairie was a primary component of Michigans historic oak-pine barrens ecosystem. However, sand prairie has been all but eliminated in the state. Our restoration experiment, established in 2009 in the Manistee National Forest, examines the influence of variable seeding rates of warm season grasses on plant community development. Initial results show that high grass seeding rates (10,000 seeds/m2) have had a positive impact on plant community development by increasing native species cover, richness, and diversity while also decreasing non-native species cover, richness, and diversity. Data from July 2013 will also be evaluated to determine if the positive impacts of this methodology are sustained. Results from this study can be used to elucidate ecologically successful and economically efficient seeding approaches in plant community restoration
Correlation of insertion torques with bone mineral density from dental quantitative CT in the mandible
- …