Insight into the Exemplary Physical Properties of Zn-Based Fluoroperovskite Compounds XZnF3 (X = Al, Cs, Ga, In) Employing Accurate GGA Approach: A First-Principles Study.

Using the full-potential linearized augmented plane wave (FP-LAPW) method, dependent on density functional theory, the simple cubic ternary fluoroperovskites XZnF3 (X = Al, Cs, Ga, In) compound properties, including structural, elastic, electronic, and optical, are calculated. To include the effect of exchange and correlation potentials, the generalized gradient approximation is applied for the optimization operation. This is identified, when we are changing the metallic cation specified as "X" when shifting to Al from Cs, the value of the bulk modulus is found to increase, showing the rigidity of a material. Depending upon the value of the bulk modulus, we can say that the compound AlZnF3 is harder and cannot be compressed as easily as compared to the other three compounds, which are having a lower value of the bulk modulus from AlZnF3. It is also found that the understudy compounds are mechanically well balanced and anisotropic. The determined value of the Poisson ratio, Cauchy pressure, and Pugh ratio shows our compounds have a ductile nature. From the computation of the band structure, it is found that the compound CsZnF3 is having an indirect band of 3.434 eV from (M-Γ), while the compounds AlZnF3, GaZnF3, and InZnF3 are found to have indirect band gaps of 2.425 eV, 3.665 eV, and 2.875 eV from (M-X), respectively. The optical properties are investigated for radiation up to 40 eV. The main optical spectra peaks are described as per the measured electronic structure. The above findings provide comprehensive insight into understanding the physical properties of Zn-based fluoroperovskites.

New spectrophotometric methods for the determination of moxifloxacin in pharmaceutical formulations.

Two rapid, simple and sensitive spectrophotometric methods for the quantitative analysis of moxifloxacin (MOX) in pharmaceutical formulations have been described. The first method (A) involves reaction of MOX with 1,2-naphthoquinone-4-sulphonate (NQS) in alkaline medium (pH 11.0) which results in an orange-coloured product exhibiting maximum absorption (lambda(max)) at 411 nm. The second method (B) is based on the oxidation of the MOX with a known excess of cerium (IV) sulfate and the residual oxidant is determined by treating with a fixed amount of methyl orange, and measuring the absorbance at 507 nm. The molar absorptivities for methods A and B were 4.9 x 10(3) and 6.5 x 10(4) L mol(-1) cm(-1), respectively. Under the optimized reaction conditions, Beer's law correlation of the absorbance with MOX concentration was obtained in the range of 2.5-20 and 0.5-30 microgmL(-1) for method A and B respectively. The intra-day precision expressed as relative standard deviation (RSD) was < 1.6% for both methods. The methods were validated in terms of accuracy and precision and were successfully applied to the determination of MOX in its pharmaceutical dosage form. The proposed methods are useful for routine analysis of MOX in quality control laboratories.