Pratik Kumar Das- Ph.D
- Assistant Professor at Indian Institute of Engineering Science and Technology, Shibpur
Pratik Kumar Das
- Ph.D
- Assistant Professor at Indian Institute of Engineering Science and Technology, Shibpur
Looking for collaboration
About
10
Publications
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63
Citations
Introduction
Room Temperature superconductivity, crystal structure prediction
Current institution
Additional affiliations
March 2014 - February 2016
Publications
Publications (10)
Hydrous minerals contribute largely to the transport and distribution of water into the mantle of earth to regulate the process of deep-water cycle. Brucite is one of the simplest layered dense hydrous mineral belonging to MgO-SiO2-H2O ternary system, which contains significant amount of water in the form of OH- groups, spanning a wide range of pre...
Motivated by the wide-band-gap semiconductor properties of Zn-monochalcogenides (Zn-X; X:S, Se and Te), especially for their crucial industrial applications, we use a first-principles approach to investigate the B3 (zinc blende type) to B1 (rock salt type) structural transitions in this series of compounds as a function of pressure and temperature....
Titanite (CaTiSiO5) is a naturally occurring silicate phase, recently recognised as a potential material for immobilization of nuclear wastes, high-end ceramic lining and optical device development. The silicate undergoes a pressure-induced structural transition (P21/c to C2/c) at ~3.5 GPa, which we confirm from density function perturbation theory...
The subsolidus phase diagram of silica in the 80–220 GPa pressure range was determined by density functional theory (DFT). The transition pressures calculated using the generalized gradient approximation (GGA) in the static limit (at 0 K, without zero point vibrational energy) for the β-stishovite (CaCl2-structure) to seifertite and the seifertite...
Coffinite (USiO4) and thorite (ThSiO4) are conspicuous radiogenic silicates in the geonomy. They form U1-xThxSiO4(uranothorite) solid solutions in zircon-type phase. Investigating the phase-evolution of these minerals is of utmost significance in realizing their applicability in the front-as well as at the back-end of nuclear industries. We carried...
Our density functional study reveals a peculiar relation between the normalized Th content i.e. Th/(U+Th) and the hydrostatic pressure enforcing zircon to reidite type transition in uranothorite solid solution. We found that the transition pressure exhibits a minimum when Th/(U+Th) = 0.50 i.e. when the unit cell contains equal amount of U and Th. A...
Olivine [(Mg, Fe)2SiO4] and pyroxene [(Mg, Fe)Si2O6] are naturally occurring silicate phases. Both the phases crystallize with orthorhombic symmetry, displaying ordering of Mg²⁺ and Fe²⁺ in their non-equivalent octahedral lattice sites (M1, M2). We address two major issues: (1) how far an inversion of the cation ordering: type I (Mg²⁺ in M1; Fe²⁺ i...
Naturally occurring zinc sulfide (ZnS) contains a substantial amount of iron (Fe) in its crystal structure. This study explores the possible effects of such Fe impurity on the physical properties of its two phases: B3 and B1, crystallizing in a cubic system with zinc blend (ZB, space group: F-43m) and rock salt (RS, space group: Fm-3m) structures....
Using DFT calculations, this study investigates the pressure-dependent variations of elastic anisotropy in the following SnO2 phases: rutile-type (tetragonal; P42/mnm), CaCl2-type (orthorhombic; Pnnm)-, α-PbO2-type (orthorhombic; Pbcn)- and fluorite-type (cubic; Fm-3m). Experimentally, these polymorphs undergo sequential structural transitions from...
Questions
Questions (5)
Hi,
First thank you for reading my post.
I have calculated the isothermal elastic constant by using QHA. Now I want to get the adiabatic elastic constants.I know the conversion factor but confused about the term "derivative of entropy with respect to strain".
I am using the strain-energy relations to calculate the 3 elastic constant for cubic MgO. I used 3 different deformation matrices to get those elastic constant. I used phonopy for the QHA calculation. So from phonopy output I can get the temperature vs entropy for a particular deformation but not the strain. So it will be of great help if anyone suggest me on how to get the ∂S/∂eii (eii= component of strain tensor).
Regards,
Pratik
I am working on 28 atom system. I need a primitive cell with 7 atoms. How should I get a primitive cell or primitive lattice vectors for this structure? I have the .cif file. Is there any way to get the primitive cell from this?
Thanks is advance.
I want to calculate the piezoelectric tensor of a material. Is there any possible ways to calculate it through Quantum Espresso?
Any suggestion is welcome.Thanks in advance.
I want to get a optimized orthorhombic structure using quantum espresso by the energy volume curve. Firstly I have some previously reported value of a, b ,c. I have already made a structure using VESTA. When I incorporate this data into espresso and run a scf calculation, it is giving me a high pressure and not the minimum energy. I have already written a script for calculating energy with changing a, another two for changing b/a and c/a . But in all the case, there is a difference between the lowest pressure and lowest energy in the energy vs volume curve. Can any one suggest me any way out to solve this problem?
Thank you in advance
Atom # 1: total charge = 9.9425, s = 0.4115, p = 0.7846, d =
8.7464,
spin up = 5.3347, s = 0.2000, p = 0.3710, d =
4.7637,
spin down = 4.6079, s = 0.2115, p = 0.4136, d =
3.9827,
polarization = 0.7268, s = -0.0115, p = -0.0426, d =
0.7810,
Atom # 2: total charge = 11.0206, s = 0.4441, p = 1.0158, d =
9.5607,
spin up = 5.4973, s = 0.2188, p = 0.4993, d =
4.7792,
spin down = 5.5233, s = 0.2253, p = 0.5164, d =
4.7815,
polarization = -0.0260, s = -0.0065, p = -0.0171, d =
-0.0023,
Spilling Parameter: 0.0010
Atom # 1: total charge = 9.9425, s = 0.4115, p = 0.7846, d =
8.7464,
spin up = 5.3347, s = 0.2000, p = 0.3710, d =
4.7637,
spin down = 4.6079, s = 0.2115, p = 0.4136, d =
3.9827,
polarization = 0.7268, s = -0.0115, p = -0.0426, d =
0.7810,
Atom # 2: total charge = 11.0206, s = 0.4441, p = 1.0158, d =
9.5607,
spin up = 5.4973, s = 0.2188, p = 0.4993, d =
4.7792,
spin down = 5.5233, s = 0.2253, p = 0.5164, d =
4.7815,
polarization = -0.0260, s = -0.0065, p = -0.0171, d =
-0.0023,
Spilling Parameter: 0.0010
