The Diamine Cation Is Not a Chemical Example Where Density Functional Theory Fails

In a recent communication, Weber and co-workers presented a surprising study on charge-localization effects in the N,N'-dimethylpiperazine (DMP+) diamine cation to provide a stringent test of density functional theory (DFT) methods. Within their study, the authors examined various DFT methods and concluded that "all DFT functionals commonly used today, including hybrid functionals with exact exchange, fail to predict a stable charge-localized state." This surprising conclusion is based on the authors' use of a self-interaction correction (namely, complex-valued Perdew-Zunger Self-Interaction Correction (PZ-SIC)) to DFT, which appears to give excellent agreement with experiment and other wavefunction-based benchmarks. Since the publication of this recent communication, the same DMP+ molecule has been cited in numerous subsequent studies as a prototypical example of the importance of self-interaction corrections for accurately calculating other chemical systems. In this correspondence, we have carried out new high-level CCSD(T) analyses on the DMP+ cation to show that DFT actually performs quite well for this system (in contrast to their conclusion that all DFT functionals fail), whereas the PZ-SIC approach used by Weber et al. is the outlier that is inconsistent with the high-level CCSD(T) (coupled-cluster with single and double excitations and perturbative triples) calculations. Our new findings and analysis for this system are briefly discussed in this correspondence.Comment: Accepted by Nature Communication

A Method for Combining Experimentation and Molecular Dynamics Simulation to Improve Cohesive Zone Models for Metallic Microstructures

Fracture processes within a material begin at the nanometer length scale at which the formation, propagation, and interaction of fundamental damage mechanisms occur. Physics-based modeling of these atomic processes quickly becomes computationally intractable as the system size increases. Thus, a multiscale modeling method, based on the aggregation of fundamental damage processes occurring at the nanoscale within a cohesive zone model, is under development and will enable computationally feasible and physically meaningful microscale fracture simulation in polycrystalline metals. This method employs atomistic simulation to provide an optimization loop with an initial prediction of a cohesive zone model (CZM). This initial CZM is then applied at the crack front region within a finite element model. The optimization procedure iterates upon the CZM until the finite element model acceptably reproduces the near-crack-front displacement fields obtained from experimental observation. With this approach, a comparison can be made between the original CZM predicted by atomistic simulation and the converged CZM that is based on experimental observation. Comparison of the two CZMs gives insight into how atomistic simulation scales

Cinco libros, dos prólogos y cuatrocientos sesenta y cinco capítulos para Tirant lo Blanch

Abordo en este artículo las características de la división textual de la versión anónima de la novela de Joanot Martorell que imprimió Diego de Gumiel en 1511, con el objetivo, a mi juicio, de ofrecer a sus lectores una obra que se amoldara al patrón de los libros de caballerías que tanto éxito empezaban a gozar ya a fines de la primera década del siglo XV

Resurgence of \u3ci\u3eNilaparvata lugens\u3c/i\u3e (Stål) Populations as Influenced by Method and Timing of Insecticide Applications in Lowland Rice

Resurgence of Nilaparvata lugens (Stål) after insecticide application is a common phenomenon in rice in South and Southeast Asia. Among other insecticides inducing resurgence, carbofuran, decamethrin, and methyl parathion were selected for this study. Of the various methods of carbofuran application tested, foliar sprays were most active in inducing resurgence. Extent of resurgence was highly influenced by time of insecticide application. Sprays of methyl parathion and decamethrin applied 50 and 65 days after transplanting (DT) induced resurgence in the third generation of N. lugens at ca. 90 DT, whereas earlier applications had little effect. The cause(s) for resurgence was not definitely established, but stimulation of N. lugens reproduction appeared to be of more significance than destruction of natural enemies

Eficácia de endectocidas em infestações naturais por Cochliomyia hominivorax (Mosca-varejeira) em bezerros no Pantanal

Todos os endectocidas injetáveis testados reduzem significativamente a ocorrência de miíases umbilicais. Entretanto, por sua maior eficácia, o uso de produtos à base de doramectina é recomendável no manejo extensivo de bezerros recém-nascidos no Pantanal.bitstream/item/37464/1/CT90.pd

Avaliação de extratos vegetais na prevenção e tratamento de Miíases Umbilicais em bezerros no Pantanal.

Devido a características ambientais e de manejo (grandes propriedades, pastagens extensas, rebanhos numerosos, mão-de-obra deficitária, etc.), as miíases umbilicais figuram dentre os principais problemas sanitários de bezerros no Estado. Esta situação é substancialmente agravada no Pantanal devido a problemas de infraestrutura, dificuldade de acesso e de manejo, determinando expressivas perdas à pecuária da região.bitstream/CPAP-2010/57494/1/CT89.pd

Temperature and seed moisture content affect electrical conductivity test in pea seeds.

Este trabalho objetivou avaliar o efeito do teor de água inicial das sementes de ervilha e da temperatura na eficiência do teste de condutividade elétrica