Ab-Initio Calculation of the Metal-Insulator Transition in Sodium rings and chains and in mixed Sodium-Lithium systems

We study how the Mott metal-insulator transition (MIT) is influenced when we deal with electrons with different angular momenta. For lithium we found an essential effect when we include $p$-orbitals in the description of the Hilbert space. We apply quantum-chemical methods to sodium rings and chains in order to investigate the analogue of a MIT, and how it is influenced by periodic and open boundaries. By changing the interatomic distance we analyse the character of the many-body wavefunction and the charge gap. In the second part we mimic a behaviour found in the ionic Hubbard model, where a transition from a band to a Mott insulator occurs. For that purpose we perform calculations for mixed sodium-lithium rings. In addition, we examine the question of bond alternation for the pure sodium system and the mixed sodium-lithium system, in order to determine under which conditions a Peierls distortion occurs.Comment: 8 pages, 7 figures, accepted Eur. J. Phys.

Calculation of the static and dynamical correlation energy of pseudo-one-dimensional beryllium systems via a many-body expansion

Low-dimensional beryllium systems constitute interesting case studies for the test of correlation methods because of the importance of both static and dynamical correlation in the formation of the bond. Aiming to describe the whole dissociation curve of extended Be systems we chose to apply the method of increments (MoI) in its multireference (MR) formalism. However, in order to do so an insight into the wave function was necessary. Therefore we started by focusing on the description of small Be chains via standard quantum chemical methods and gave a brief analysis of the main characteristics of their wave functions. We then applied the MoI to larger beryllium systems, starting from the Be6 ring. First, the complete active space formalism (CAS-MoI) was employed and the results were used as reference for local MR calculations of the whole dissociation curve. Despite this approach is well established for the calculation of systems with limited multireference character, its application to the description of whole dissociation curves still requires further testing. After discussing the role of the basis set, the method was finally applied to larger rings and extrapolated to an infinite chain

Struktur Kepemilikan, Mekanisme Tata Kelola Perusahaan, Dan Biaya Keagenan Di Indonesia (Studi Empirik Pada Perusahaan Di Bursa Efek Indonesia)

This study is to examine the effect of corporate governance (the owners\u27s character and thegovernance mechanism) on agency cost. This research shows that family ownership, financialinstitution ownership, government ownership, and foreign ownership have negative effects onagency cost that is proxied as managerial operation cost and or as assets turnover, compared topublic ownership. Furthermore, ownership concentration of at least 5 percent each is not provento effect the agency cost. Results of other examination show that the proportion of independentboard and the number of board meetings have negative effects to the agency cost that is proxiedas assets turnover. However, these two variables and the number of audit committee meetinghave the opposite effect to the agency cost when it is proxied as managerial operation cost.Theseinconsistencies are caused by the ineffective implementation of corporate governance mechanismin Indonesia even after 10 years of implementation

Investigation of metal-insulator like transition through the ab initio density matrix renormalization group approach

We have studied the Metal-Insulator like Transition (MIT) in lithium and beryllium ring-shaped clusters through ab initio Density Matrix Renormalization Group (DMRG) method. Performing accurate calculations for different interatomic distances and using Quantum Information Theory (QIT) we investigated the changes occurring in the wavefunction between a metallic-like state and an insulating state built from free atoms. We also discuss entanglement and relevant excitations among the molecular orbitals in the Li and Be rings and show that the transition bond length can be detected using orbital entropy functions. Also, the effect of different orbital basis on the effectiveness of the DMRG procedure is analyzed comparing the convergence behavior.Comment: 12 pages, 14 figure

Factorization of numbers with Gauss sums: II. Suggestions for implementations with chirped laser pulses

We propose three implementations of the Gauss sum factorization schemes discussed in part I of this series: (i) a two-photon transition in a multi-level ladder system induced by a chirped laser pulse, (ii) a chirped one-photon transition in a two-level atom with a periodically modulated excited state, and (iii) a linearly chirped one-photon transition driven by a sequence of ultrashort pulses. For each of these quantum systems we show that the excitation probability amplitude is given by an appropriate Gauss sum. We provide rules how to encode the number N to be factored in our system and how to identify the factors of N in the fluorescence signal of the excited state.Comment: 22 pages, 7 figure

Correlated ab-initio calculations for ground-state properties of II-VI semiconductors

Correlated ab-initio ground-state calculations, using relativistic energy-consistent pseudopotentials, are performed for six II-VI semiconductors. Valence ($ns,np$) correlations are evaluated using the coupled cluster approach with single and double excitations. An incremental scheme is applied based on correlation contributions of localized bond orbitals and of pairs and triples of such bonds. In view of the high polarity of the bonds in II-VI compounds, we examine both, ionic and covalent embedding schemes for the calculation of individual bond increments. Also, a partitioning of the correlation energy according to local ionic increments is tested. Core-valence ($nsp,(n-1)d$) correlation effects are taken into account via a core-polarization potential. Combining the results at the correlated level with corresponding Hartree-Fock data we recover about 94% of the experimental cohesive energies; lattice constants are accurate to \sim 1%; bulk moduli are on average 10% too large compared with experiment.Comment: 10 pages, twocolumn, RevTex, 3 figures, accepted Phys. Rev.

Iman Kristiani Kepada Allah yang Satu

Penghayatan iman umat Kristiani begitu khas. Umat Kristiani percaya kepada Allah yang Satu. Untuk menjelaskan pernyataan ini, penulis menggunakan bahan bacaan berupa bagian buku tulisan Joseph Ratzinger (Paus Benediktus XVI) yang berjudul Prolegomena to the Subject of God. Berbicara mengenai Allah yang Satu dalam kepercayaan Kristiani, kita tentu tidak dapat melepaskan diri dari konsep yang khas, yakni Allah Tritunggal

Differences In Led Values In Dengue Fever Patients With Hemoconcentration And Not Hemoconcentration

Background: Patients with dengue fever with hemoconcentration will experience plasma tearing (loss of plasma protein) which will affect the value of the Erythrocyte Sedimentation Rate (LED). Plasma proteins that play a role in influencing the value of the Sedimentation Rate (LED) are fibrinogen and globulins. An erythrocyte sedimentation (LED) examination measures the degree of erythrocyte deposition in a blood sample over a period of time. LEDs are sensitive but not specific tests. Purpose: To determine the difference in LED values of DHF patients with hemoconcentration and not hemoconcentration. Methods: Observational analytic, 30 samples with criteria for dengue fever patients with hemoconcentration and not hemoconcentration were examined at the Clinical Pathology Laboratory of Haji Hospital Surabaya in March - April 2019. The study used an independent t test with SPSS 16.0 program to determine whether there were differences in LED values in dengue fever patients with hemoconcentration and not hemoconsetration. Results: The results of the Independent t test showed that there were significant differences between the results of the erythrocyte sedimentation rate in patients with dengue fever with hemoconcentration and not hemoconsetration with Sig. (2-failed) of 0.00 (p <0.005). Conclusion: There are significant differences in sediment rate results with the Westergreen blood method in patients with dengue fever who experience hemoconcentration and who do not experience hemoconcentration

On the calculation of complete dissociation curves of closed-shell pseudo- onedimensional systems via the complete active space method of increments

The method of increments (MoI) has been employed using the complete active space formalism in order to calculate the dissociation curve of beryllium ring-shaped clusters Be n of different sizes. Benchmarks obtained through different quantum chemical methods including the ab initio density matrix renormalization group were used to verify the validity of the MoI truncation which showed a reliable behavior for the whole dissociation curve. Moreover we investigated the size dependence of the correlation energy at different interatomic distances in order to extrapolate the values for the periodic chain and to discuss the transition from a metal-like to an insulator-like behavior of the wave function through quantum chemical considerations