Investigation on the third-order nonlinear optical properties of a novel 2-methylimidazolium tetrachlorocadmate (2MITCC) single crystal for optical limiting applications

Abstract

Nonlinear optical (NLO) single-crystalline materials are of significant interest due to their potential to meet the increasing demands for diverse practical applications, such as optical communication, optoelectronics, laser technology, optical modulation, data storage, electro-optical switching, and optical limiting. For the development of nonlinear optical (NLO) materials, compositions of 2-methylimidzole (2MI), cadmium chloride (CdCl₂) and hydrochloric acid (HCl) were used to synthesis with a dimension of 13 × 2 × 2 mm³ metal inorganic material of 2-methylimidazolium tetrachlorocadmate (2MITCC) and the crystals were grown using Slow Evaporation Solution Technology. The 2MITCC crystal belongs to monoclinic P2₁/c space group and the unit cell values (a = 9.0274(9) Å, b = 14.8945(14) Å, c = 7.4458(7) Å, β = 94.119(3)° and Z = 4). The structure of the 2MITCC crystal was depicted by the WinXMorph program. Powder XRD analysis was employed to examine the purity and crystalline structure of the crystalline planes. EDS analysis confirms the molecules of C, N, Cd and Cl in the 2MITCC crystal. The 2MITCC single crystal was recorded. UV-DRS transmittance analysis revealed exceptional transparency (> 98%), along with a cut-off edge at 248 nm and an E_g value of 5 eV. The FTIR analyses were used to identify the vibrational groups. SEM studies reveal the surface morphology of the 2MITCC crystal. TG–DTA studies examined the thermal stability of the 2MITCC. The temperature-dependent dielectric constant and dielectric loss were measured over a frequency range of 1 Hz to 1 MHz. Third-order NLO property of 2MITCC was investigated by the Z-scan method using a Q-Switched Nd: YAG laser with 532 nm and it was revealed that the crystal has a reverse saturable absorption (RSA) effect. All these results demonstrate that the metal–organic crystal 2MITCC is promising for NLO applications.