Paramagnetism Definition and 34 Threads

  1. S

    A Understanding the Limitations of Electron Spin Resonance

    Hello, I have a question regarding the limitations of Electron Spin Resonance (ESR). I've read somewhere that ESR cannot detect radicals with short lifetimes. I'm trying to understand why is that? For example: a highly dynamic system like liquid sulfur at high temperatures, where sulfur...
  2. C

    Entropy of spin-1/2 Paramagnetic gas

    As we know, dipole can be only arranged either parallel or anti-parallel with respect to applied magnetic field ## \vec{H} ## if we are to use quantum mechanical description, then parallel magnetic dipoles will have energy ## \mu H ## and anti-parallel magnetic dipoles have energy ## -\mu H##...
  3. WeiShan Ng

    I [Stat Phy] What does exhausting the states of a system mean?

    I was reading the *Statistical Physics An Introductory Course* by Daniel J.Amit and need some help to understand a certain passage: In an isolated composite system of two paramagnetic system: System a with ##N_a## spins and a magnetic field ##H_a ## System b with ##N_b## spins and a...
  4. WeiShan Ng

    Average magnetic moment of the system

    I was reading the statistical physics textbook and was really confused with the notation: I don't understand the last part of the section. Why is that \sum_{\sigma = \pm1} \sigma P(\sigma) equals to \left< \sigma \right>? And what does \left< \sigma \right> actually mean? Is it the average...
  5. M

    Applying the grand canonical ensemble to a magnetic system

    Homework Statement Consider a system with N sites and N particles with magnetic moment m. Each site can be in one of three states: empty with energy 0, occupied by one particle with energy 0 (in the absent of magnetic field) or occupied by two particles with anti parallel moments and energy ε...
  6. M

    Paramagnetic system: computing number of microstates

    Homework Statement We are given a paramagnetic system of N distinguishable particles with 1/2 spin where we use N variables s_k each binary with possible values of ±1 where the total energy of the system is known as: \epsilon(s) = -\mu H \sum_{k=1}^{N} s_k where \mu is the magnetic moment...
  7. P

    I Diamagnetism vs. paramagnetism in solid state

    I am studying some solid state physics, in particular magnetism; I have a few questions about the explanations. My understanding is that paramagnetism is primarily an effect of the electron's spin-angular momentum: an unpaired electron will have a dipole moment which preferentially aligns with...
  8. DeathCheese

    Calculate force on Permanent Magnet near a Paramagnetic surface

    Hello all, new here but plan to stick around for a while. I am currently trying to make a sensor that can detect if a material below it is paramagnetic. I believe paramagnetic is the proper term, but it needs to detect if the force exerted by permanent magnet is above a certain threshold. The...
  9. C

    What causes paramagnetism and diamagnetism

    Paramagnetism: How does having an unpaired electron attract it into a magnetic field. Why not repel? Is there any reason or we just know from experiment? Diamagnetism: If the electron spins and therefore magnetic fields cancel, what is causing it to repel from a magnetic field? If it is...
  10. S

    Magnetic levitation using eddy current

    Hi, I am working on an experiment to investigate the effect of electrical conductivity of the metals on the levitating force produced. Basically the concept is this: when a metal plate is placed on top of a solenoid (but not touching), as the a.c. flows in the solenoid the change in magnetic...
  11. J

    Magnetic moment of paramagnetic crystal

    Hello, I've been having some trouble with a paramagnetism problem from my Statistical Mechanics class textbook (F. Mandl, Statistical Physics, 2nd edition, p. 25). The problem is as follows 1. Homework Statement 2. Homework Equations 1. The temperature parameter \displaystyle{ \beta =...
  12. U

    Curie-Weiss Paramagnetism susceptibility

    Homework Statement (a) Show the curie-weiss behaviour. (b) Estimate ##\lambda## and ##B_e## and exchange energy.[/B] Homework EquationsThe Attempt at a Solution Part(a) Since even when applied field is zero, ##B_{total} \neq 0## which gives rise to ##M\neq 0##. This is a fundamental...
  13. R

    Exploring Paramagnetism in Molecules: Be2, B2, C2, and N2

    Homework Statement Assuming 2s-2p mixing is not operative, the paramagnetic species among the following is 1. Be2 2. B2 3. C2 4. N2 Homework Equations NA The Attempt at a Solution Not able to understand the statement "2s -2p mixing is not operative". Can you help? Paramagnetism is a specie...
  14. I

    How Do Unpaired Electron Orbits React to External Magnetic Fields?

    Please confirm & answer the following: An atom exposed to an external B-field will experience both a torque on its orbitals (paramagnetism), and a change in orbital velocities and thereby a change in the magnetic momenta of the orbits (diamagnetism). When the atom has all paired electrons...
  15. G

    How Does the Additional Electron in (O2)- Affect Its Paramagnetism?

    O2 has two unpaired electrons, therefore it's quite strong paramagnetism. But what about (O2)-, the negatively charged O2 ion? Am I right in assuming that due to the additional electron one unpaired electron will get together with it, so that overall it should still be paramagnetic, but...
  16. D

    Difference between paramagnetism and ferromagnetism

    Homework Statement I've been asked to describe the difference between these two, but I'm a but confused. In my book, it says that paramagnetism is weaker than ferromagnetism, but I don't see why. If I'm not mistaken, both paramagnetism and ferromagnetism arise from the fact that you...
  17. A

    Finding the Partition Function in Paramagnetism

    Homework Statement I was given a Hamiltonian H = -\muB\sumcos\alpha_{i} where the sum is over i from i = 1 to i = N I need the partition function given this Hamiltonian. Homework Equations The Attempt at a Solution I tried using the classical approach where Z_{N} =...
  18. L

    Paramagnetism of Free Ions. Sign problem.

    Energy of system of magnetic dipoles is ##E_H=-\mu_0 \vec{\mu}\cdot \vec{H}=-\mu_0\mu_zH## why sign ''-''? and ##\mu_z=-g_J\mu_Bm## Again why ''-'' sign ? ##z## is choosen to be quantization direction, and along that direction is applied field ##H##.
  19. P

    Q about diff. between ferro and paramagnetism under a strong mag field

    Hi From what I understand ferromagnetic materials have domains that contain magnetic dipoles that are almost all parallel to each other. However these domains have random directions. Under a magnetic field the domains in the ferromagnetic material that are magnetized in the field direction...
  20. C

    Ferromagnetism versus Paramagnetism

    I know that the different magnetic properties arise from the spin of the electron, I also did some determinations whether a molecule is paramagnetic or diamagnetic (using MO theory), but I don't know how to make a difference between ferromagnetism and paramagnetism. Could someone explain it? And...
  21. P

    Pauli Paramagnetism vs Curie Paramagnetism

    As far as I am aware, Pauli Paramagnetism applies to electrons in bands while Curie Paramagnetism applies to localised electrons. Pauli Paramagnetism is usually much weaker because only the electrons near the Fermi Surface can change its spin to align with the magnetic field. On the other hand...
  22. F

    Confusion regarding the Boltzman distribution as it applies to paramagnetism

    I'm currently in an introductory thermal physics course, and today we learned about the Boltzmann factor and how to use it to calculate various quantities with the corresponding probability distribution. All was going well until we got to the subject of paramagnetism. We supposed a system of...
  23. G

    Paramagnetism of O2: Electronic Configuration Explained

    what is the electronic configuration in 02 that makes it a paramagnetic material?
  24. B

    Please check- Statistical paramagnetism.

    Homework Statement A paramagnetic crystal of N ions of spin 1/2, at constant temperature T, is subjected to a magnetic field B. Using the fact that the Helmholtz Free Energy is minimized show that the mean magnetic moment M is: \mu tanh\frac{\mu B}{kT} Homework Equations Magnetic...
  25. M

    Atomic Paramagnetism: Understanding m_j Sublevels

    Hey everyone, I've noticed that when paramagnetism is derived in the context of stat mech, we only consider the energy levels of the perturbation. Essentially, we take the fine structure of hydrogen, and we perturb it with a B-field, causing the weak zeeman effect to split the energy levels...
  26. J

    The difference between diamagnetism and paramagnetism?

    Hi, I am struggling to see the difference in the origins of diamagnetism and paramagnetism. My understanding of things is that the electrons orbitting an atom constitute a tiny circular current loop, which corresponds to a magnetic dipole moment pointing normal to the plane of that loop...
  27. S

    Need help finding References for Paramagnetism and Superparamagnetism

    Hello, I was wondering if anyone could recommend some really good sources which discuss Paramagnetism and Superparamagnetism in a fairly rigorous manner. I have been using Kittel, 7th Edition of Intro to Solid State Physics, as a reference source. I was hoping to find another...
  28. F

    Pauli paramagnetism - signs are driving me crazy

    Hi all, I am looking into the discussions of Pauli paramagnetism (arising from free neutral fermions with spin 1/2) in chapter 11.6 of K. Huang's Stat. Mech. (II ed) and in chapter 31 of Ashcroft and Mermin's Solid State Physics. It seems to me that these books do not agree on signs. So...
  29. S

    What is magnetism, diamagnetism and paramagnetism?

    I need help understanding both of these terms. I know that diamagnetism is when the valence electrons of the material are paired and repel a magnetic field. Does that mean it repels like the North side of a magnet to another North side of a magnet? Or is it they don't attract at all...
  30. K

    Logs rearranging, relates to paramagnetism

    [SOLVED] Logs rearranging, relates to paramagnetism Homework Statement I want to show that NlnN - n1ln(n1) - n2ln(n2) is equal to: -N{(n1/N)ln(n1/N) + (n2/N)ln(n2/N)} apparently i can do this by the artifice of adding and subtracting the term n1lnN and then regrouping. Homework...
  31. U

    Thermodynamics - Paramagnetism proof

    Show that the entropy of a two-state paramagnet, expressed as a function of temperature, is S=Nk[ln(2coshx)-xtanhx], where x=μB/kT. Check that this formula has the expected behavior as T->0 and T->infinity. Not even sure where to start...
  32. P

    Explaining paramagnetism, diamagnetism, and ferromagnetism

    I have a short paper to write this weekend and my physics book doesn't do a very good job of explaining paramagnetism, diamagnetism, and ferromagnetism. Anyone know a good website that gives similarities and differences among those 3 types of magnetism? Thank you.
  33. N

    Report on either Diamagnetism or Paramagnetism

    I am doing an extra-credit report on either Diamagnetism or Paramagnetism, just wondering if any of you can give me any resources on either subject.
  34. A

    How Do Diamagnetism and Paramagnetism Relate to Lenz's Law?

    Simple question, kind of. I know that paramagnetic materials, when in the presence of a magnetic field will have its dipoles orient with the field while diamagnetic materials when introduced to a magnetic field orient opposite to the field. I've read that this has something to do with Lentz's...
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