Microwave study of vibration-rotation spectrum of carbon suboxide C3O2 in the 300- to 1000-GHz frequency range

Abstract The submillimeter wave spectrum of the C 3 O 2 molecule was investigated within the 300- to 1000-GHz range. The measured frequencies include 256 lines belonging to the ground vibrational state and to four excited vibrational states of ν 7 . Rotational and centrifugal constants and constants of “l” splitting for the ground and excited states ν 7 1 , 2 ν 7 2 , 3 ν 7 3 , 4 ν 7 4 as well as frequencies of purely vibrational transitions ν 7 1 ← 0; 2 ν 7 2 ← ν 7 1 ; 3 ν 7 3 ← 2 ν 7 2 ; 4 ν 7 4 ← 3 ν 7 3 together with their correlation matrix were determined.