# libZFRelaxation

- libZFRelaxation
- 1 Introduction
- 2 Isotropic static Gaussian broadened randomly oriented internal fields
- 3 Isotropic static Lorentzian broadened randomly oriented internal fields
- 4 Static Gaussian distributed fields with uniaxial anisotropy

# 1 Introduction

`libZFRelaxation` is a collection of `C++` classes using the `musrfit` `user-function interface` in order to facilitate the usage in conjunction with `musrfit`. The classes contained in this library implement the calculation of some additional zero-field μSR relaxation functions which are not built-in into `musrfit`.

In the following the use of the implemented functions is shortly introduced—for details on the applicability and derivation of these functions please refer to the original publications.

If these classes prove useful and results obtained through them are part of scientific publications, an acknowledgement of the use of the library is appreciated.

# 2 Isotropic static Gaussian broadened randomly oriented internal fields

E. I. Kornilov and V. Yu. Pomjakushin, Phys. Lett. A 153, 364–367 (1991), doi: 10.1016/0375-9601(91)90959-C

`musrfit` THEORY-block line:

    userFcn libZFRelaxation ZFMagGss 1 2 3 4

The parameters are:

1. the precessing fraction α (= 2/3 in the article),
2. the "internal frequency" ν (MHz),
3. the "transverse depolarization rate" σT (μs-1),
4. the "longitudinal depolarization rate" σL (μs-1) (= 0 in the article).

# 3 Isotropic static Lorentzian broadened randomly oriented internal fields

M. I. Larkin, Y. Fudamoto, I. M. Gat, A. Kinkhabwala, K. M. Kojima, G. M. Luke, J. Merrin, B. Nachumi, Y. J. Uemura, M. Azuma, T. Saito, and M. Takano, Physica B 289–290, 153–156 (2000), doi: 10.1016/S0921-4526(00)00337-9

`musrfit` THEORY-block line:

    userFcn libZFRelaxation ZFMagExp 1 2 3 4

The parameters are:

1. the precessing fraction α (= 2/3 in the article),
2. the "internal frequency" ν (MHz),
3. the "transverse depolarization rate" aT (μs-1),
4. the "longitudinal depolarization rate" aL (μs-1) (= 0 in the article).

# 4 Static Gaussian distributed fields with uniaxial anisotropy

G. Solt, Hyperfine Interactions 96, 167–175 (1995), doi: 10.1007/BF02066280

where

and

`musrfit` THEORY-block line:

    userFcn libZFRelaxation UniaxialStatGssKT 1 2 3

The parameters are:

1. σ1 (μs-1),
2. σ3 (μs-1),
3. Θ (°).

-- BMW & AS

This topic: MUSR > WebHome > MusrFit > BmwLibs > LibZFRelaxation
Topic revision: r2 - 10 Jul 2011 - 17:50:10 - BastianWojek
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