Knowledge Bank

Rotational spectra have been observed with a Flygare FTMW $spectrometer1$ for a number of hydrogen-bonded trimers, most of which are linear and have the HCN dimer as a subunit. Spectroscopic constants have been determined, usually for several isotopic species of each trimer. Their values are given below for the Itain species. Symmetries, hydrogen-bond lengths and the separation of torsional and charge redistribution effects on the quarupolar hyperfine structure of $\mathrm{<mrow\; data-mjx-texclass="ORD">14</mrow>}N(Xa)$ will be discussed. [FIGURE]