**5.2 Current challenges**

coefficients or increase in its order can fix the problem. In such cases for a complete and satisfactory refinement process, the estimation of background should be skipped and linear interpolation and subtraction procedure should be followed. While background is generally eliminated in refinement process, the peak base shapes are essentially a part of background and therefore at higher 2θ, more care should be taken in estimating the background. This is why background fitting using linear interpolation by cubic-splines should be generally avoided. The asymmetric peak shape especially at higher 2θ (where peak intensities are generally low) and non-careful background estimation or subtraction can affect the relative intensity of

**Figure 4(a), (b)** and **(c)** respectively show contribution of amorphous, nanoscale and micrometer-scale phase towards background in LaMnO3 samples.

More time spent on measurement less significant background. This is somewhat misleading the background does not actually change with increased time spent per step. It is the increase in the number and intensity of counts per peak that increases which visibly smoothens the background. The precautions for background contribution during data collection have been discussed previously are almost entirely

*XRD pattern for (a) mostly amorphous, (b) nanoscale and (c) micrometer-scale phase of LaMnO3. The hump visible in (a) is a characteristic of amorphous phase, while the noisy background in (b) is characteristic of*

peaks and therefore degrade the overall refinement quality.

**5.1 Precautions/explanations**

*Advanced Ceramic Materials*

**Figure 4.**

**258**

*nanoscale phase due to low intensity counts.*

We are essentially in a nano-technological world right now and most of the materials applications around us have transitioned from bulk to micro to nanoscale. The complexities associated with the nanoscale XRD have also risen noticeably [52–55]. Nanoscale background contribution, irregular peak shapes, non-correctable preferred orientation/asymmetry parameters, sometimes odd combination of Lorentzian and Gaussian peak parameters. The porosity and reduced dimensionality (especially, 1D, 2D materials) are very difficult to characterize via normal XRD procedures.
