Measurements of rotational transitions and hyperfine structure in PH2D

New rotational transition frequencies and measurements of hyperfine structure on two transitions are reported for PH₂D. All observed transitions are Q branch (ΔJ = 0) so only two independent rotational constants are obtained. These are A-C = 46 593.44 ± 0.67 MHz and κ(A-C) = 2B-A-C = ?34 545.9 ± 1.3 MHz. Nine transitions were fit to these parameters and the distortion parameter D_JK to obtain D_JK = 4.30 ± 0.04 MHz. Hyperfine structure due to spin-rotation interactions was observed on the 1₁₀ ← 1₁₁ transition at 6 024.645 MHz and on the 4₁₄ ← 4₀₄ transition at 20 815.334 MHz. Spin-rotation tensor components obtained are $\text{(M}{}_{\mathrm{aa}}\text{+ M}{}_{\mathrm{bb}}\text{)}\text{2}\text{=}\text{(M}{}_{\mathrm{aa}}\text{+ M}{}_{\mathrm{cc}}\text{)}\text{2}\text{= ?98 ± 3}\text{kHz}$.