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Questions tagged [magnetism]

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9 votes
3 answers
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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}...
Camps's user avatar
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20 votes
1 answer
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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 ...
SalvaCardona's user avatar
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15 votes
1 answer
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Is Heisenberg model or in its simplier form Ising model a good approximation to study magnetic systems?

Heisenberg model $$\hat{H}=-\sum_{\langle i j\rangle}J\hat{S}_i\hat{S}_j$$ And in its simplified version, the Ising model $$\hat{H}=-\sum_{\langle ij\rangle}J\hat{S}_i^z\hat{S}_j^z$$ are widely ...
Paulie Bao's user avatar
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25 votes
3 answers
536 views

What are examples of materials that closely correspond to the Heisenberg model?

I use the antiferromagnetic Heisenberg model all the time: $ H = J \sum \limits_{\langle i,j \rangle} \vec S_i \cdot \vec S_j$ What are some examples of materials that are well-described by this ...
taciteloquence's user avatar
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 ...
Camps's user avatar
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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 ...
Thomas's user avatar
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17 votes
2 answers
548 views

Is there any good review paper on the density matrix renormalization group (DMRG) method?

I would appreciate if someone could recommend me good review literature on the density matrix renormalization group (DMRG) method, especially for magnetic systems.
Paulie Bao's user avatar
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15 votes
3 answers
1k views

Magnetism and Topology

Can magnetism and topological insulating behavior coexist in a material? If yes, can someone refer to a recent work?
Shahid Sattar's user avatar
14 votes
1 answer
3k views

How to do spin polarization calculations using Quantum ESPRESSO?

I am currently new to DFT calculations in Quantum ESPRESSO. Though, I have read some research papers for determining spin polarization and Half-metallicity in certain Heusler alloys. These research ...
UJM's user avatar
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13 votes
3 answers
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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 ...
Anoop A Nair's user avatar
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11 votes
1 answer
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Is the "Final Magnetic moment" in the materials project repository same as the "total magnetization" value in Quantum ESPRESSO output files?

I'm quite new to spin-polarized DFT and have been trying to study $BaVSe_{3}$ which is ferromagnetic (with a Final Magnetic Moment of 0.052 Bohr Mag) as per the Materials Project repository [picture 1]...
Anoop A Nair's user avatar
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10 votes
1 answer
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How to calculate the exchange matrix of a bilayer magentic system?

I have been using the Vampire atomistic simulation software for a while and it has a useful simulation for predicting the curie temperature. But in order to do that I need the exchange matrix of Co-...
Anoop A Nair's user avatar
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9 votes
2 answers
615 views

How to visualize MuMax3 shapes?

I'm new to micromagnetics and the finite difference method. The mumax3 software lets you create a variety of geometric shapes. I would like to create a core-shell particle to study magneto-electric ...
Anoop A Nair's user avatar
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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 ...
astha's user avatar
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