New Organic Crystalline Material Close to Nodal-Line Materials: α′-STF₂IBr₂

Round 1

Reviewer 1 Report

There is no doubt that topological materials are a hot topic of contemporary solid state physics. The Authors have made an effort to synthesize a new compound which potentially could be a new topological material. They prepared a new organic charge-transfer complex  α’-STF₂IBr₂ which is very similar to the well-established zero-gap conductor formed by the same donor STF, namely α-STF₂I₃. Crystal structure, electrical conductivity, and magnetic properties of α’-STF₂IBr₂ were studied as a function of temperature and discussed in comparison with  α-STF₂I₃. The experimental studies were supplemented by tight-binding band calculations which were also compared with analogous data for α-STF₂I₃. The measurements and calculations were performed very carefully, paying a great attention to all details. The Author’s accuracy and pedantry analysis deserve admiration. The conclusion that the complex α’-STF₂IBr₂  is close to a nodal-line-type semimetal is very interesting and important. I agree with Author’s opinion that “This finding will accelerate the successive findings of nodal-line materials …”. I think that it is an important and well-written paper which will attract attention of researchers working in the field of topological materials. Therefore, I strongly suggest to accept the manuscript for publication in Crystals. My only remark is that Fig. 2 is divided into two parts on page 5 and page 6, hindering thus its analysis.     

Author Response

Thank you very much for your high evaluation of our manuscript. Now Fig. 2 is resized to be placed within a page.

Reviewer 2 Report

The manuscript presents results of the  studies of mixed-valence salt of  bis(ethylenedithio)diselenadithiafulvalene) with Br2i- anion. The authors compared structure, magnetic and conductance properties of this salt with closely related salt with triodide anions. The work seems sound and coul be published    

English is OK, but the presentation could be improved to make results more easy to comprehend.  

Author Response

Thank you very much for your high evaluation of our manuscript. We have revised the presentation to be more comprehensive. The actual changes are recorded in the revised manuscript using “Track changes” of Microsoft Word.

Reviewer 3 Report

It may benefit readers if you add a 2-dimensional band structure of the material with and without pressure effects. 

IN some places a minor grammar check may be needed. 

Author Response

Thank you very much for your high evaluation of our manuscript. Additionally, we thank the valuable suggestion that it may benefit readers if we add the two-dimensional band structures with and without pressure effects for comparison. However, the atomic parameters (crystal structures) at high pressure are not available for this material now, which prevents the band calculation. Thus, the band structure at high pressure and comparison with the ambient pressure band structure should wait for an upcoming paper. Regarding the minor grammar check, we have checked and revised the English in the entire text.