A circular photonic crystal fiber including slotted core (SC-PCF) is proposed for chemical sensing application. The full vectorial finite-element method (FEM) has been applied for a numerical investigation by altering geometrical metrics in the interval of wavelengths from 0.7 to 1.5 мm. An optimized structure is selected by investigating the proposed PCF. The main focus of this research is to find out the hazardous and toxic chemicals. The proposed structure shows a relative sensitivity of 47.08% and a confinement loss of 3.11 × 10−5 dB/m at the same time.