*3.7. True Density Determination*

The true density of samples was determined using a helium gas pycnometer (Pycno 30, Smart Instruments, Mumbai, India) as per the previously reported protocol [34]. Before analysis, the samples were pre-dried at 40 ◦C for 24 h in a vacuum oven to avoid the e ffect of residual moisture on true density measurement. The pre-dried sample, su fficient to fill 3/4 of the volume of the sample cell, was weighed (1.5–2.5 g) and transferred into the sample cell. The first pressure reading (P1) was recorded after passing a pressurized pure helium gas in a known reference volume into the reference cell. Then, the pressurized helium gas was allowed to flow from the reference cell into the sample cell. This led to drop in the initial pressure that recorded as second pressure reading (P2). These values of P1 and P2 put into Equation (1) to calculate the true volume Vp.

$$\mathbf{V\_P} = \left(\frac{\mathbf{P\_1}}{\mathbf{P\_2}} - 1\right) (\mathbf{V\_c} - \mathbf{V\_r}) \tag{1}$$

where Vc and Vr are the cell volume and reference volume having values of 18.9522 and 11.9587 cm<sup>3</sup>/g, respectively. True density was calculated by dividing the sample mass by true volume (VP) value.

### *3.8. Preparation of Compacts for Studying Bulk Deformation Behavior*

Compacts were prepared by compressing 400 mg of crystalline powder using di fferent compaction pressure in a hydraulic press (Type KP, Sr. No. 1125, Kimaya Engineers, Maharastra, India). The applied dwell time for compaction preparation was 1.0 min using a 13.0 mm punch die set (round, flat-faced punch). Di fferent compression forces were applied manually to achieve a range of compaction pressures from 37-222 MPa. The actual compaction pressure was determined from the know value of the applied hydraulic load (Force) and the surface area of the flat punch-die set used for compression. Equation (2) was used for converting the applied load into compaction pressures.

$$\mathbf{P} = \frac{\mathbf{F}}{\mathbf{A}}\tag{2}$$

where, F is the applied hydraulic load (Newton, N), and A is the surface area of the flat punch-die set (in mm2). Prior to analysis, the prepared compacts were stored for 48 h under ambient conditions to allow for relaxation of any residual stress. Subsequently, compacts were analyzed for weight, thickness, and breaking force measurement.

### *3.9. Calculation of Tensile Strength and Porosity*

The assessment of tensile strength (σ) value in bulk deformation profiling helps to eliminate the undesirable e ffect of variable tablet thickness on a measured breaking force. Therefore, tensile strength (σ) was calculated using Equation (3), based on breaking force (F), table diameter (d) and tablet thickness (t).

$$
\sigma = \frac{2\text{F}}{\pi \text{dt}}\tag{3}
$$

where σ is the tensile strength in MPa, F is the observed breaking force in N, d is the diameter in mm, and t is thickness of the compact in mm.

Tablet hardness tester (Erweka, TBH 20, USA) was used to measure the breaking force (F) of all of the compacts. Digital caliper (CD-6 CS, Digimatic Mitutoyo Corporation, Kanagawa, Japan) was used to measure tablet diameter and thickness. The porosity (ε) of the compacts was calculated using Equation (4), from tablet density (ρc) and true density of the powder (ρt). ρc is calculated from the weight and volume of the resulting tablet, while ρt is measured by helium pycnometer as described above.

$$
\varepsilon = 1 - \frac{\rho\_{\rm c}}{\rho\_{\rm t}} \tag{4}
$$
