The microwave spectrum of the doubly deuterated cyanomethyl radical (D₂CCN) in its ground electronic state (²B₁) has been observed for the lowest four rotational transitions (N_Ka,Kc = 1_0,1–0_0,0, 2_0,2–1_0,1, 2_1,2–1_0,1 and 2_1,1–1_1,0) using a Fourier transform microwave spectrometer in combination with a pulsed discharge nozzle. A total of 394 hyperfine components were measured and subjected to a least squares analysis which allowed determining twelve hyperfine constants for nitrogen and deuterium nuclei. With this new set of molecular constants we obtained accurate predictions for low N rotational transitions with hyperfine structure, and searched for this species in TMC–1.

双氘化氰基甲基自由基 (D ₂ CCN) 在其基电子态 ( ² B ₁ )的微波光谱中观察到最低的四个旋转跃迁 ( N _Ka,Kc  = 1 _0,1 –0 _0,0 , 2 _0,2 –1 _0,1 , 2 _1,2 –1 _0,1和 2 _1,1 –1 _1,0) 使用傅里叶变换微波光谱仪与脉冲放电喷嘴相结合。总共测量了 394 个超精细组分，并进行了最小二乘分析，这允许确定氮和氘核的 12 个超精细常数。通过这组新的分子常数，我们获得了对具有超精细结构的低N旋转跃迁的准确预测，并在 TMC-1 中搜索了该物种。