Skip to main content

Questions tagged [magnetism]

For questions about magnetic systems and materials

Filter by
Sorted by
Tagged with
2 votes
0 answers
19 views

Investigation of ferro, ferri, antiferro, para and dia magnetism using QE

Can Quantum ESPRESSO be used to investigate ferromagnetism, ferrimagnetism, antiferromagnetism, diamagnetism, and paramagnetism? If so, could you please elaborate on how these types of magnetism are ...
3 votes
0 answers
25 views

Magnetocrystalline Anisotropy Energy

How should one proceed in VASP to compute the magnetoanisotropy energy effectively?
7 votes
1 answer
131 views

How to check whether spin orbit coupling is strong or weak?

I am doing spin-orbit coupling (SOC) calculations using VASP. I had done a magnetic anisotropy calculation, but I do not know how to check whether the SOC is weak or strong. Any help would be highly ...
3 votes
1 answer
74 views

Is there a minimum inter-defect distance when introducing point defects into a 2D structure, ensuring defects don't exhibit significant interactions?

I am currently conducting a DFT investigation into the magnetism of 2D materials by introducing defects into the structure. Is there a minimum distance I should maintain between two defects in ...
4 votes
0 answers
153 views

Electronic Convergence issues for DFT+U+SOC in VASP for magnetic materials

While performing DFT+U+SOC calculation in VASP for the material $\mathrm{Mn_3Sb}$ my calculation is not at all converging. Here I am attaching the necessary input files. I have come across some ...
2 votes
1 answer
73 views

Visualizing magnetic moments of Quantum espresso input/output files

I am looking for a software/website that can visualize atomic structure of my quantum espresso input/output files with magnetic moments. Any help will be highly appreciated. Thanks in advance!
3 votes
1 answer
84 views

Does VASP include energy penalty contribution in OUTCAR energy of constrained moment calculation?

In VASP, one can use I_CONSTRAINED_M to constrain local magnetic moments to a certain direction in SOC calculations. However, this comes at the cost of adding an energy penalty to the total energy. ...
8 votes
1 answer
104 views

What is the difference between non self consisent calculation and single-shot calculation?

I am new to density functional theory. My goal is to calculate magnetic anisotropy energy using the force theorem. For that, I have been told that one can run a self-consistent calculation with some ...
2 votes
0 answers
186 views

Clarifying local magnetic moment axes in VASP: cartesian vs crystal (for MAGMOM/M_CONSTR)

In VASP, one can set the local magnetic moments of each ion in a non-collinear SOC calculation along a certain direction using the MAGMOM/M_CONSTR tags. The manual linked to states that these local ...
5 votes
0 answers
56 views

How to calculate anisotropic exchange J $J_{xy}, J_{xz}, J_{yz}, J_{yx}, ...$ using 4-state mapping and DFT?

In this review, the authors present several schemes to calculate various quantities like single-ion anisotropy, DMI, and anisotropic exchange J using DFT. For instance, the DMI term in the y-direction ...
9 votes
3 answers
344 views

Is it possible to calculate/estimate the value of the J parameter to be used in the Heisenberg/Ising Hamiltonians?

Studying magnetic systems, two frequently used approximations are the Heisenberg and Ising models (a discussion about these approximations can be read here): \begin{equation} \tag{Heisenberg} \hat{H}...
6 votes
1 answer
149 views

How is magnetization of a solid obtained from electron density in a DFT framework?

What's the theory behind these kind of calculation? What are keywords and concepts I have to search for?
4 votes
1 answer
85 views

Modelling 2D semiconductor heterostructures including one magnetic layer with QE

I want to compute the electronic structure of a heterostructure composed of two 2D monolayers. I am stacking a TMD monolayer on top of a magnetic 2D monolayer. Both of them are semiconductors. Do I ...
2 votes
1 answer
45 views

How is it possible for amorphous metal to have good magnetic properties with randomly arranged atoms?

Cross-posted on Physics.SE. It makes sense that something like grain-oriented electrical steel would have good magnetic properties (e.g., magnetic permeability). I'm envisioning magnetic field lines ...
7 votes
1 answer
297 views

What are Crystal Electric Field Parameters?

What does the following notation mean? $$A_{20}\left<r^2\right> = -100 \mathrm{K}$$ Where $A_{20}$ is termed a Crystal Electric Field Parameter. I often see this notation when reading papers on ...
19 votes
1 answer
589 views

How to evaluate spin exchange parameters of a magnetic material using DFT?

I think we have to calculate total energies using different FM, AFM configurations and solve a set of linear equations. How to arrive at the set of equations for any given structure? An example from ...
3 votes
1 answer
82 views

How to find magnetic materials in terms of magnetic point groups?

Are there any methods to find materials in terms of the assigned magnetic point group? For example, I know the magnetic point groups $6'mm'$ and $6'22'$, and I want to find the corresponding ...
8 votes
1 answer
590 views

How to change the magnetization direction in Quantum ESPRESSO?

I have a magnetic crystal system. I want to calculate the total energy of the system if the magnetization direction is aligned in different directions such as [110], [010]. By default Quantum ESPRESSO ...
3 votes
0 answers
79 views

Does hysteresis depend on anisotropy? [closed]

I was reading a manual on magnetic materials. It discussed the origin of hysteresis of ferromagnetic materials, but it is not clear to me whether or not it depends on anisotropy. I understand that the ...
1 vote
1 answer
616 views

nspin and starting_magnetization in Quantum Espresso

In Quantum Espresso, there is a parameter called nspin, which I understand to include in INPUT if there is a paramagnetic species, like $\ce{Fe}$. Thus, we also ...
5 votes
1 answer
581 views

Issues converging with DFT+U and magnetism in Quantum ESPRESSO

Dear fellow matter modelers, I am trying to model the zig-zag antiferromagnetic material $\alpha$-RuCl$_3$ using QUANTUM ESPRESSO. My end goal is to include DFT + U + SOC, however, including too many ...
4 votes
1 answer
148 views

Is there any useful application to estimating the expectation value for an Ising model without magnetic field?

In the same line of thoughts as this post, I am trying to understand better in which cases quantum computers could be useful to simulate materials under some constraints on what the quantum computer ...
2 votes
0 answers
2k views

Setting MAGMOM in VASP for possible Magnetic configurations [closed]

I have been working with a material in which Cu has an unpaired electron due to which the material can exist in various magnetic configurations. I wish to see how various properties change as I switch ...
4 votes
0 answers
89 views

Why can't DFT calculate the energy of magnetic diatomic molecules accurately?

I am trying to calculate the reaction enthalpy change of $\ce{2H2 + O2->2H2O}$, my plan is to calculate the energy of $\ce{H2, O2 \text{and} H2O}$, respectively, then do the simple math. But I find ...
9 votes
1 answer
859 views

PT-symmetry leading to spin-degenerate band structures

I am trying to understand the fundamental physics of a kind of problem. I will introduce a specific example and then list some of the broader qualms I hold. I have observed many band structures, be it ...
6 votes
1 answer
1k views

How to calculate the magnetic anisotropy energy using the VASP code?

I want to calculate the magnetic anisotropy energy of the CrI$_3$ monolayer which has 8 atoms per unit cell. I have understood from VASPWIKI that there are two steps: A standard SCF collinear ...
12 votes
2 answers
410 views

Predicting magnetic moment of a metal complex computationally

Recently, for entrance exams, I have been dealing with a lot of weird compounds. One of them is $\ce{K3[Mn(CN)6]}$. The objective was to predict the magnetic moment of the above complex. I predict ...
14 votes
0 answers
148 views

Handling multiple self-consistent solutions with DFT+U

It is well-established that within the DFT+U framework, one can achieve several self-consistent solutions with greatly varying energies for the same exact magnetic ordering. In 2010, Meredig et al. ...
6 votes
0 answers
67 views

Modeling magnetic field of permanent magnet: Where to start? [closed]

I would like to model magnetic field of a permanent magnet like this one magnet . Ideally, I would like to do it python or any other language. I would like to start with some simple geometry and some ...
14 votes
0 answers
251 views

Orbital magnetization in periodic solids

The orbital magnetization in periodic solids has been nicely described by the so-called modern theory of magnetization [1,2,3,4]. $$\tag{1} \mathcal{M}_{orb} = -\frac{1}{2} \Im \sum_{n,\mathbf{k}} f_{...
5 votes
0 answers
96 views

How to set the AFM configuration in this doped monolayer system? [closed]

The figure below illustrates a 2x2x1 supercell of transition metal-doped CrI$_3$ monolayer. The red, green, and black atoms represent Cr, I, and transition metal atoms, respectively. I want to ...
6 votes
0 answers
252 views

How to define ferrimagnetism in Quantum ESPRESSO [closed]

I would like to pick this problem from my previous post See link. I am clear about how to define antiferromagnetism in QE. Here I am with another issue. I am ...
7 votes
1 answer
86 views

Which one should be investigated first? dynamic stability or magnetic stability?

I would like to investigate the stability of $\ce{VI_3}$ monolayer, but I am confused about whether I start directly by performing Phonon spectrum calculation, or I should first investigate the ...
8 votes
0 answers
87 views

Band unfolding for magnetic systems [closed]

I'm trying to study the electronic structure of a 1D antiferromagnetic (in which the spin is associated with copper atoms) system, via spin-polarized calculations. The unit cell dimensions are ...
9 votes
1 answer
283 views

How is SYMPREC used to determine symmetries compatible with local magnetic moments in VASP?

In DFT calculations using vasp, symmetry analysis are performed to determine space group symmetries at first, if symmetrization is turned on, such as ISYM = 2. When magmoms are set in INCAR, ...
5 votes
1 answer
197 views

How to make ferro, feri and antiferro magnetic structure for QE

I have below &SYSTME information from my input file ...
6 votes
0 answers
43 views

Is it possible to calculate the variation of magnetization M(T) for a diluted magnetic semiconductor? [closed]

Is there any simulation program (for example a DFT package) to determine the variation of magnetization M(T) for dilute magnetic semiconductors or doped semiconductors with different concentrations of ...
8 votes
2 answers
216 views

Magnetic Transition Pymatgen Error

I am trying to simulate the change in magnetic moments during a ferromagnetic to antiferromagnetic transition. ...
6 votes
1 answer
255 views

How is the material $\ce{\alpha-NaMnO2}$ pronounced?

I am a theoretical physicist, so I am not very familiar with chemical names. The material I am interested in is $\ce{\alpha-NaMnO2}$. Would that be pronounced alpha sodium manganese dioxide? Is it ...
13 votes
3 answers
380 views

Are there any codes to study magnetic materials?

I have used a few codes for studying magnetic materials (specifically core-shell nanoparticles with an AFM shell and an FM core). These are: Vampire: For the calculation of curie temperature via ...
10 votes
1 answer
264 views

Why does the S squared value have no meaning in Density Functional Theory?

It is not the first time that I stumble upon the affirmation that spin and the $S^2$ value, under DFT, has no "real physical meaning". Why? If that is true, why are we using it all the time ...
8 votes
1 answer
138 views

What measured quantity can be associated to the value of the J parameter in the Heisenberg/Ising hamiltonians?

This question is related to other one here in the MatterModelingSE: Is it possible to calculate/estimate the value of the J parameter to be used in the Heisenberg/Ising hamiltonians? Here J is the ...
10 votes
1 answer
377 views

How can I calculate the J value in an antiferromagnetic material?

I am new to DFT, especially in doing DFT for magnetic materials. I recently came across this paper which indicated the calculation of the J value in the case of antiferromagentic materials as per the ...
21 votes
4 answers
3k views

Is it possible to calculate the Curie temperature for magnetic systems?

Using DFT calculations we can know the electronic and magnetic property of the system at 0 K. I am wondering if there is any computational method to know the curie temperature of magnetic materials? ...
20 votes
1 answer
351 views

Calculation of the relative energies in a Spin Crossover material

Spin Crossover (SCO) complexes are a particular type of molecular entities which are usually formed by a metal ion (general $\ce{Fe(II)}$ or $\ce{Co(III)}$) complexed by several ligands with donor N ...
8 votes
1 answer
186 views

How to study a new material without any experimental data about it?

My question is a little bit general. I want to study a 2D monolayer material which hasn't any experimental data available, just some first principles DFT works using PBE, LDA and HSE06 (for band ...
4 votes
1 answer
621 views

How can I obtain seperate spin-up and spin-down bands while considering Spin Orbit Coupling in Quantum ESPRESSO?

I have been studying a magnetic material with SoC taken into consideration. The main aim was to obtain the band structure. when I use spin_component = 1 in the ...
7 votes
1 answer
163 views

Will there be a difference between GGA and GGA+$U$ for material with Sc element involved?

I have a material that contains the transition metal element Sc [3$d$1], and I want to know your opinions if there will be a difference between GGA and GGA+$U$ calculation. Knowing that the other ...
9 votes
2 answers
621 views

Can we consider SOC in FM materials using QE?

This is a follow-up question to my question posted here. I've been trying to study the effects of spin-orbit coupling (SOC) on the band structure of ferromagnetic (FM) material VSe$_{2}$. The input ...
6 votes
1 answer
132 views

Are these settings for HSEsol accurate enough?

I have conducted HSEsol relaxation on a monolayer unit cell of 3 atoms using VASP, with the settings below : ...