Comment on "Self-doping effects in cobalt silicide CoSi: Electrical, magnetic, elastic, and thermodynamic properties"

TL;DR

This comment critiques a previous study on CoSi, arguing that the original estimates of paramagnetic centers were significantly overstated and that the reported resistivity data lack reproducibility, undermining the original conclusions.

Contribution

It provides a critical re-evaluation of prior experimental data on CoSi, highlighting errors in paramagnetic center estimation and questioning data reproducibility.

Findings

Estimated paramagnetic center concentrations are 25-50 times smaller than originally reported.

Resistivity data across different labs are suspiciously similar, indicating possible measurement issues.

Main conclusions of the original study are unjustified due to these errors.

Abstract

In this Comment it is argued that Stishov et al. [Phys. Rev. B 86, 064433 (2012)] incorrectly estimated concentrations of (supposed) paramagnetic centers with \mu_eff = 4.8\mu_B in the investigated CoSi crystals. Correct estimation gives concentrations of such centers from 25 to 50 times smaller than reported (appr. 0.04 to 0.16% instead of appr. 2 to 4%). Also the reported data on temperature dependence of resistivity \rho(T) of four CoSi crystals prepared in different Labs are so close to each other at T = 250 to 300K that it is extremely unlikely to be reproducible for any reasonable accuracy of resistivity measurements. These and some other problems of the paper are related to the key points of the authors argumentation. As a result their main conclusions become unjustified.