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My comments concern the uncertainties in the crystallographic part of the commented paper. The lattice parameters are incorrectly evaluated and the symmetry is not monoclinic. Therefore, the subsequent data on other measurements have limited value. The correct structural data are presented indicating the coexistence of two cubic phases which differ in crystallite size. A size-induced phase transition can be supposed to exist in the studied sample. [ABSTRACT FROM AUTHOR]

My comments concern the errors in the crystallographic part of a recent paper published in this journal entitled “Structural and electrical analysis of polycrystalline ceramic PbCaBiNbO6” by A.K. Panda et al., J. Mater. Sci.: Mater. Elektron. 34, 1640 (2023). The true chemical composition of the studied sample is very different from PbCaBiNbO6 as proposed by authors in their paper. A comparison with three similar compounds was presented indicating that the samples are mixtures of (at least) two crystals Therefore, the subsequent data on other measurements are not on the sample composition the authors have identified and have limited value. [ABSTRACT FROM AUTHOR]

My comments concern the uncertainties in the crystallographic part of the commented paper. The correct crystal structure should be described as NaNbO3:K,Bi,Ti instead of solid solution proposed by authors and described as 0.075(K0.5Bi0.5TiO3)–0.925(NaNbO3). Moreover, the studied sample has no ferroelectric properties; the P–E loop is of “banana”-type, only. [ABSTRACT FROM AUTHOR]

My comments concern the error in the lattice parameters and chemical composition of BiHoZnCeO6 perovskite published in the commented paper. The most probable composition of the studied sample is CeO2:Bi,Ho,Zn. [ABSTRACT FROM AUTHOR]

This comment is on errors involved in the evaluation of lattice parameters in the paper by B. Pati et al., J. Mater. Sci.: Mater. Electron. 24, 1608 (2013). The correct values of the trigonal lattice parameters of Ba3(VO4)2 (≡ Ba3V2O8) should be a = 5.778(2) and c = 21.27(2) Å. [ABSTRACT FROM AUTHOR]

My comments concern some errors in the crystallographic part of the commented paper. The diffraction patterns are erroneously analysed and the final data on the structure (symmetry and unit cell parameters) are different than those supposed in the paper. [ABSTRACT FROM AUTHOR]

This comment on the above three papers argues that the crystals should be of sillenite type and the correct formula should be Bi25FeO39:MTi (M = Co or Ni) instead of BiFeO3. Due to the doping, a new type of unit cell, previously unknown, was proposed for such crystals. There is also about 15% of a secondary phase, BiFeO3, in the sample. This part of the sample should be responsible for the magnetic properties recorded. [ABSTRACT FROM AUTHOR]

The new analysis of the previously published data on the nanocrystalline CaYTiNbO7:Eu indicates an occurrence of the size-induced structural phase transition like in other nanocrystalline phosphors of pyrochlore structure. [ABSTRACT FROM AUTHOR]

This comment argues that the paper published by R. Kumar, K. Dev Singh, and R. Kumar, entitled "Effect of Sr substitution on the structural properties of LaCrO3 perovskite" [J. Mater. Sci.: Mater. Electron. 33, 12039 (2022)] contains errors in the XRD section and in the crystallite size determinations. The correct approach is provided in this comment. [ABSTRACT FROM AUTHOR]

In the commented paper, there are some questionable data which should be explained or corrected by the Authors, Thangamani et al. In this comment, I have tried to pinpoint incorrect data or inconsistencies and to verify the correctness of the data presented in the crystallographic part of the paper. [ABSTRACT FROM AUTHOR]

My comments concern the severe errors in the crystallographic part of the commented paper. The correct formula is proposed to be Bi1-xGdxFeO3 instead of BiFe0.95Gd0.05O3. Thus, the actual composition of the studied crystal is not known. Furthermore, it is evident that the sample contains at least three different phases. The subsequent studies do not present the properties of the title compound. [ABSTRACT FROM AUTHOR]

The article presents a comment on the study on structural, optical and morphology of hexagonal zinc oxide nanorods. It examines the focus of the concern on the use of texture coefficient in the case of powder sample that contains separate grains. It also recognizes the systematic errors found in the evaluation of the crystallite size from Scherrer formula which resulted to the standard deviation of a range of few nanometers.

A review of the article "Structural, morphological and magnetic characters of PVP coated ZnFe2O4 nanoparticles" by R. Sagayaraj and colleagues is presented.