Tuning the Dirac Cone of Bilayer and Bulk Structure Graphene by Intercalating First Row Transition Metals using First Principles Calculations

Modern nanoscience has focused on two-dimensional (2D) layer structure materials which have garnered tremendous attention due to their unique physical, chemical and electronic properties since the discovery of graphene in 2004. Recent advancement in graphene nanotechnology opens a new avenue of creating 2D bilayer graphene (BLG) intercalates. Using first-principles DFT techniques, we have designed 20 new materials \textit{in-silico} by intercalating first row transition metals (TMs) with BLG, i.e. 10 layered structure and 10 bulk crystal structures of TM intercalated in BLG. We investigated the equilibrium structure and electronic properties of layered and bulk structure BLG intercalated with first row TMs (Sc-Zn). The present DFT calculations show that the 2$p_z$ sub-shells of C atoms in graphene and the 3$d_{yz}$ sub-shells of the TM atoms provide the electron density near the Fermi level controlling the material properties of the BLG-intercalated materials. This article highlights how the Dirac point moves in both the BLG and bulk-BLG given a different TM intercalated materials. The implications of controllable electronic structure and properties of intercalated BLG-TM for future device applications are discussed. This work opens up new avenues for the efficient production of two-dimensional and three-dimensional carbon-based intercalated materials with promising future applications in nanomaterial science.Comment: 60 pages, 9 figures. arXiv admin note: text overlap with arXiv:1701.03936 by other author

Possible cosmological implications in electrodynamics due to variations of the fine structure constant

Astronomical observations are suggesting that the fine structure constant varies cosmologically. We present an analysis on the consequences that these variations might induce on the electromagnetic field as a whole. We show that under these circumstances the electrodynamics in vacuum could be described by two fields, the ``standard'' Maxwell's field and a new scalar field. We provide a generalised Lorentz force which can be used to test our results experimentally.Comment: 7 pages, no figures. Accepted for publication in Rev. Mex. Fis. (Some extra information included, references added and small corrections made to the original version

Winners and Losers of Tax Competition in the European Union

This paper quantifies the macroeconomic effects of capital income tax competition in the European Union using a two-country neoclassical dynamic general equilibrium model. This model incorporates three key externalities of tax competition: the relative price externality, the wealth distribution externality and the fiscal solvency externality. We consider tax strategies limited to the class of time-invariant taxes and allow governments to issue debt to smooth the tax burden. The analysis starts from a pre-tax-competition equilibrium calibrated to represent the United Kingdom and Continental Europe (France, Germany and Italy) using data from the early 1980s, just before the European integration of financial markets. When labor taxes adjust to maintain fiscal solvency, competition does not trigger a “race to the bottom” in capital taxes. The UK makes a large welfare gain and cuts its capital tax. Continental Europe increases both labor and capital taxes and suffers a large welfare loss. These results are consistent with evidence showing that over the last two decades the UK lowered its capital tax, while Continental Europe increased both capital and labor taxes. When consumption taxes adjust to maintain fiscal solvency, there is a “race to the bottom” in capital taxes but both the UK and Continental Europe are better off than in the pre-tax-competition equilibrium. The gains from coordination in all of these experiments are trivial.

A Quantitative Analysis of Tax Competition v. Tax Coordination under Perfect Capital Mobility

Theory predicts that strategically-determined tax rates induce negative externalities across countries in relative prices, the wealth distribution and tax revenue. This paper studies the interaction of these externalities in a dynamic, general equilibrium environment and its effects on quantitative outcomes of tax competition in one-shot games over capital income taxes between two governments that set time-invariant taxes and issue debt. Strategic payoffs correspond to welfare gains net of the cost of transitional dynamics in a standard neoclassical two-country model with exogenous balanced growth. The model is calibrated to European data for the early 1980s starting from a benchmark with symmetric countries. When countries compete over capital taxes adjusting labor taxes to maintain fiscal solvency, the Nash equilibrium replicates calibrated taxes, suggesting that European taxes can be the outcome of Nash competition. When consumption taxes are adjusted to maintain fiscal solvency, competition triggers a “race to the bottom” in capital taxes but this outcome is welfare-improving relative to calibrated taxes. Sensitivity analysis shows that competition can produce a “race to the top” in capital taxes and that the United Kingdom can benefit from tax competition with Continental Europe. Surprisingly, the gains from coordination in all of these experiments are small.

Governance in Southeast Asia: Issues and Options

This paper attempts to analyze governance systems in Southeast Asia and proposes some policy suggestions that can improve governance practices in the region. To put the discussion on governance systems in a proper context, the paper discusses the governance and growth nexus in Southeast Asia; describes the operating governance systems in Southeast Asia; analyzes economic governance, more specifically in the areas of economic management and growth, revenue generation, social spending, access to services, cost of doing business, and corporate governance; and examines political governance focusing on the rule of law and judicial independence, conflict management, and voice participation.governance, development program, corruption

Winners and Losers of Tax Competition in the European Union

This paper quantifies the macroeconomic effects of capital income tax competition in the European Union using a two-country neoclassical dynamic general equilibrium model. This model incorporates three key externalities of tax competition: the relative price externality, the wealth distribution externality and the fiscal solvency externality. We consider tax strategies limited to the class of time-invariant taxes and allow governments to issue debt to smooth the tax burden. The analysis starts from a pre-tax-competition equilibrium calibrated to represent the United Kingdom and Continental Europe (France, Germany and Italy) using data from the early 1980s, just before the European integration of financial markets. When labor taxes adjust to maintain fiscal solvency, competition does not trigger a race to the bottom' in capital taxes. The UK makes a large welfare gain and cuts its capital tax. Continental Europe increases both labor and capital taxes and suffers a large welfare loss. These results are consistent with evidence showing that over the last two decades the UK lowered its capital tax, while Continental Europe increased both capital and labor taxes. When consumption taxes adjust to maintain fiscal solvency, there is a race to the bottom' in capital taxes but both the UK and Continental Europe are better off than in the pre-tax-competition equilibrium. The gains from coordination in all of these experiments are trivial.

Governance in Southeast Asia: Issues and Options

This paper attempts to analyze governance systems in Southeast Asia and proposes some policy suggestions that can improve governance practices in the region. To put the discussion on governance systems in a proper context, the paper discusses the governance and growth nexus in Southeast Asia; describes the operating governance systems in Southeast Asia; analyzes economic governance, more specifically in the areas of economic management and growth, revenue generation, social spending, access to services, cost of doing business, and corporate governance; and examines political governance focusing on the rule of law and judicial independence, conflict management, and voice participation.governance, development program, corruption

The Finnish Great Depression: From Russia with Love

During the period 1991-93, Finland experienced the deepest economic downturn in an industrialized country since the 1930s. We argue that the culprit behind this Great Depression was the collapse of Finnish trade with the Soviet Union, because it induced a costly restructuring of the manufacturing sector and a sudden, large increase in the cost of energy. We develop and calibrate a multi-sector dynamic general equilibrium model with labor market frictions, and show that the collapse of Soviet-Finnish trade can explain key features of Finland's Great Depression. We also show that Finland's Great Depression mirrors the macroeconomic dynamics of the transition economies of Eastern Europe. These economies experienced a similar trade collapse. However, as a western democracy with developed capital markets and institutions, Finland faced none of the large institutional adjustments that other transition economies experienced. Thus, by studying the Finnish experience we isolate the adjustment costs due solely to the collapse of Soviet trade.business cycles, depression, trade, Soviet, reallocation, multi-sector model

Design of Covalent Organic Frameworks for Methane Storage

We designed 14 new covalent organic frameworks (COFs), which are expected to adsorb large amounts of methane (CH_4) at 298 K and up to 300 bar. We have calculated their delivery uptake using grand canonical Monte Carlo (GCMC) simulations. We also report their thermodynamic stability based on 7.5 ns molecular dynamics simulations. Two new frameworks, COF-103-Eth-trans and COF-102-Ant, are found to exceed the DOE target of 180 v(STP)/v at 35 bar for methane storage. Their performance is comparable to the best previously reported materials: PCN-14 and Ni-MOF-74. Our results indicate that using thin vinyl bridging groups aid performance by minimizing the interaction methane-COF at low pressure. This is a new feature that can be used to enhance loading in addition to the common practice of adding extra fused benzene rings. Most importantly, this report shows that pure nonbonding interactions, van der Waals (vdW) and electrostatic forces in light elements (C, O, B, H, and Si), can rival the enhancement in uptake obtained for microporous materials derived from early transition metals