levelpop.m

From Spinach Documentation Wiki
Revision as of 19:38, 6 June 2026 by Kuprov (talk | contribs) (Update function See also links and function index membership)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search

Equilibrium populations of the energy levels of a user-specified spin at the user-specified temperature. Energies are reported as fractions of kT at the temperature specified.

Syntax

    [E,P,dP]=levelpop(isotope,field,temperature)

Parameters

      isotope      - character string specifying the isotope.
                     e.g. '1H', '13C', 'E', etc.

      field        - primary magnet field in Tesla

      temperature  - spin temperature, Kelvin

Outputs

      E            - vector of level energies, frac-
                     tions of kT at the temperature
                     specified

      P            - vector of level populations

      dP           - vector of population differences
                     for adjacent levels

Examples

Free electron energy level populations at 4.0 Kelvin:

    >> [~,P]=levelpop('E',14.1,4.0)

    P =

       (1,1)       0.0087
       (2,1)       0.9913

Notes

The function is sensitive to the sign of the magnetogyric ratio - negative for electrons, positive for protons, etc.

See also

spin.m, equilibrium.m, pauli.m, carrier.m, hamiltonian.m, brokensymm.m, quad_shift.m, r1csa2tauc.m, r1n_dnp.m, r2csa2tauc.m, rlx_csa.m, rlx_dd_csa.m, rlx_dip.m, rlx_hfc.m, rlx_nqi.m, trosy_eff.m, Textbook_module

Version 2.4, authors: Ilya Kuprov