<p>In this work, CaCu₃Ti_4-xM_xO₁₂ (<i>x</i> = 0.05, M = Cr, Mo, and W) ceramic has been successfully synthesized using a semi-wet route. The phase confirmation and microstructural studies were examined by Powder X-ray Diffraction (PXRD) pattern, Raman Spectroscopy, and Scanning Electron Microscopy (SEM), respectively. The oxidation state of the individual elements present in the crystal systems was examined by X-ray Photoelectron Spectroscopy (XPS), revealing Cr³⁺/Cr⁶⁺, Mo⁴⁺/Mo⁶⁺, W⁴⁺/W⁵⁺/W⁶⁺, Cu²⁺, Ti³⁺/Ti⁴⁺, and Ca²⁺ and O^-2. The magnetic moment was found using ESR spectra observed for CCTCO, CCTMO, and CCTWO, which are 2.62 , 3.37 , and 3.38 BM, respectively. The bandgaps were observed using the Tauc Plot, found to be approximately 3.14 , 3.12 , and 3.15 eV for CCTCO, CCTMO, and CCTWO ceramics, respectively. Based on a correlation approach, a practical model explaining the relationship between electronic defects and Photoluminescence (PL) spectra was developed. Red PL emissions observed in the samples are attributed to metal vacancies, which indicate the presence of deep-level defects, while blue PL emissions are associated with shallow defects, following the trend Cr &gt; Mo &lt; W. At an applied electric field with a frequency of 1,113,760 Hz, the highest relative permittivity (εᵣ) values were 1.4×10⁶ for CCTCO, 4×10³ for CCTMO, and 5×10⁴ for CCTWO, with their corresponding tan δ values of 3, 7, and 20, respectively. The increase in dielectric constant from top to bottom in the group of transition metals can be explained by the Internal Barrier Layer Capacitance (IBLC) mechanism, where semiconducting grains are separated by insulating grain boundaries.</p>