English

Analytical calculation of the axis angle 2V from extinction measurements on the spindle stage

Computational Physics 2017-03-02 v1 Chemical Physics Data Analysis, Statistics and Probability

Abstract

A concise derivation of the "Joel equations", which allow for the determination of the axis angle 2V from measurements of extinction directions on a spindle stage, is provided starting from the wave-equation. Only analytic methods and no geometric arguments referring to stereographic projections are invoked. For error free data, the resulting equations allow for a closed form solution. If angle data with measurement error are to be used, a maximum likelihood estimation methodology is proposed, which may be solved using e.g. iterative reweighting. The method is tested with and compared to published data.

Keywords

Cite

@article{arxiv.1703.00070,
  title  = {Analytical calculation of the axis angle 2V from extinction measurements on the spindle stage},
  author = {Florian Dufey},
  journal= {arXiv preprint arXiv:1703.00070},
  year   = {2017}
}