# A new hybrid bismuth chloride semiconductor (C5H7BrN3)6(BiCl5)3: powder XRD, optical properties, and DFT investigation

## TL;DR

Scientists created a new hybrid material combining organic and inorganic parts, which could be useful for semiconductors and optoelectronics.

## Contribution

The paper introduces a new hybrid bismuth chloride semiconductor with detailed structural and optical analysis.

## Key findings

- The compound crystallizes in the triclinic space group P̄1 with a unique asymmetric unit.
- DFT calculations confirm structural parameters and vibrational assignments matching experimental IR data.
- The material has an indirect bandgap of 2.6 eV, indicating semiconducting behavior.

## Abstract

In this work, we report the synthesis and characterization of the new hybrid inorganic–organic compound (C5H7BrN3)6(BiCl5)3, which crystallizes in the triclinic space group P̄1. The crystal structure, determined from X-ray powder diffraction, reveals an asymmetric unit built from one [Bi2Cl10]4− dimer, one independent [BiCl5]2− anion, and six neutral 2,3-diamino-5-bromopyridinium molecules. This arrangement highlights the coexistence of distinct bismuth chloride units stabilized by an extensive network of hydrogen bonding and electrostatic interactions with the organic moieties. Density Functional Theory (DFT) calculations performed at the B3LYP/LANL2DZ level provide optimized structural parameters and vibrational assignments consistent with the experimental IR spectrum recorded in the 400–4000 cm−1 range. The optical properties investigated via solid-state UV-vis diffuse reflectance reveal an indirect bandgap of 2.6 eV, confirming the semiconducting behavior of the material. The combination of structural features, optical response, and theoretical insights underscores the potential of (C5H7BrN3)6(BiCl5)3 as a promising hybrid material for semiconductor and optoelectronic applications.

In this work, we report the synthesis and characterization of the new hybrid inorganic–organic compound (C5H7BrN3)6(BiCl5)3, which crystallizes in the triclinic space group P̄1.