Nikita Acharya

Structural stability and bonding in TMOs2 (TM=Sc and Y) C14 Laves phase compounds

The structural, electronic as well as bonding nature of TMOs2 (TM=Sc and Y) Laves phase compounds are studied using full potential linearized augmented plane wave (FP-LAPW) method within generalized gradient approximation (GGA). These compounds are crystallize in MgZn2-type hexagonal structure. The total energy are calculated using Birch Murnaghan’s equation of state to find the equilibrium lattice parameter (a0), Bulk modulus (B0) and pressure derivative of bulk modulus (B0) and are in good agreement with experimental results. The electronic properties reveal that ScOs2 and YOs2 are highly metallic. The charge density difference plots represent ionic as well as metallic bonding, with weak covalent character.

Effect of Si doping on ductility of RuAl intermetallics: A first principle study

Based on density functional full potential linearized augmented plane wave (FP-LAPW) method, we have investigated the structural, electronic and elastic properties of RuAlxSi1−x with Si concentration varying between 0.0 and 1.0. The exchange and correlation potential is treated by the generalized gradient approximation. The values of elastic moduli at ambient pressure are also reported. The ductility of these compounds has been analyzed using Pugh rule and Cauchys pressure. From this study we found that RuAl is brittle while all its Si doped alloys are ductile and RuAl0.75Si0.25 is found to be the most ductile. The band structure of RuAl and its alloys are also reported.

Structural, Electronic and Elastic Properties of Palladium Nitride

A systematic theoretical study of 4d transition metal nitride, PdN has been carried out using ab initio full potential LAPW method (FP-LAPW) within the generalized gradient approximation (GGA). PdN crystallizes in zinc-blende structure, which is found to be most stable one. We have calculated the ground state properties in terms of lattice constant (a0), Bulk modulus (B0) and its Pressure derivative (B0). The electronic properties such as band structure and density of states reveal that PdN is metallic in nature with large overlap of Pd-d electron at Fermi level. The elastic constant are in good agreement with previous theoretical results for zinc-blende structure.

Investigation of thermoelectricity in KScSn half-Heusler compound

The electronic and transport properties of KScSn half-Heusler (HH) compound have been investigated using first-principles density functional theory and semi classical Boltzmann transport theory. The electronic band structure and density of states (total and partial) show semiconducting nature of KScSn with band gap 0.48 eV which agree well with previously reported results. The transport coefficient such as electrical conductivity, Seebeck coefficient, electronic thermal conductivity and power factor as a function of chemical potential are evaluated. KScSn has high power factor for p-type doping and is a potential candidate for thermoelectric applications.

Structural and Electronic Properties of ScPt3 and YPt3 Intermetallic Compounds

The bonding nature as well as structural and electronic properties of cubic XPt3 (X=Sc and Y) intermetallic compounds, which crystallize in AuCu3-type structure have been investigated using a full-potential linearized augmented plane wave (FP-LAPW) method within generalized gradient approximation (GGA). The equilibrium lattice parameters (a0), bulk modulus (B), pressure derivative of bulk modulus (B’) have been obtained using optimization method. Electronic properties of these compounds have been analyzed from band structure and Fermi surfaces.

Ab-initio study of B2-type technetium AB (A=Tc, B=Nb and Ta) intermetallic compounds

The structural, electronic and elastic properties of AB type (A = Tc, B = Nb and Ta) technetium intermetallic compounds are studied using full potential linearized plane wave (FP-LAPW) method within generalized gradient approximation (GGA). The calculated lattice parameters agree well with the experimental results. The elastic constants obey the stability criteria for cubic system. Ductility for these compounds has been analyzed using the Pugh’s rule and Cauchy’s pressure and found that all the compounds are ductile in nature. Bonding nature is discussed in terms of Fermi surface and band structures.

Electronic structure, elasticity, bonding features and mechanical behaviour of zinc intermetallics: A DFT study

The structural stability, electronic structure, elastic and mechanical properties of TiZn and ZrZn intermetallics have been studied using ab-initio full potential linearized augmented plane wave (FP-LAPW) method within generalized gradient approximation for exchange and correlation potentials. The various structural parameters, such as lattice constant (a0), bulk modulus (B), and its pressure derivative (B’) are analysed and compared. The investigation of elastic constants affirm that both TiZn and ZrZn are elastically stable in CsCl (B2 phase) structure. The electronic structures have been analysed quantitatively from the band structure which reveals the metallic nature of these compounds. To better illustrate the nature of bonding and charge transfer, we have also studied the Fermi surfaces. The three well known criterion of ductility namely Pugh’s rule, Cauchy’s pressure and Frantsevich rule elucidate the ductile nature of these compounds.

First principles study on structural, electronic, elastic and thermal properties of equiatomic CoTi and CoZr

We have investigated the structural, electronic, elastic and thermal properties of CoTi and CoZr using ab-initio full potential linearized plane wave method (FP-LAPW) method within generalized gradient approximation (GGA). The calculated the ground state and electronic properties such as lattice constant (a0), bulk modulus (B0), its pressure derivative (B0’) and density of states at Fermi level N (EF) which are in good agreement with other experimental and theoretical results. The elastic constants (C11, C12 and C44) are also calculated for these compounds. Ductility has been analyzed by Pugh’s rule (B/GH) ratio and Cauchy’s pressure (C12−C44). To the best of our knowledge, the elastic and thermal properties of CoZr are calculated first time.

First principles study on structural, electronic, elastic and mechanical properties of RuAl1−xGex alloys using special quasirandom structure

We developed the special quasirandom structure to study the structural, electronic, elastic and mechanical properties of RuAl1−xGex for different composition (x= 0.25, 0.50, 0.75 and 1) using Density Functional (FP-LAPW) method. The exchange and correlation potential is treated by the generalized gradient approximation. The values of elastic constant at ambient pressure are also reported. The ductility of these compounds has been analyzed using Pugh rule and Cauchy’s pressure. From this study we found that RuAl is brittle while all its Ge doped alloys are ductile and RuAl0.25Ge0.75 is found to be the most ductile. The band structure of RuAl and its alloys are also reported.