Knowledge Bank

The pure rotational spectrum of the asymmetric top $ZrO2$ has been collected using a Fourier transform microwave spectrometer that employed a laser ablation molecular beam source. Four rotational transitions for each of five $Zr16O2$ isotopomers have been recorded. The rotational constants of the $\mathrm{<mrow\; data-mjx-texclass="ORD">90</mrow>}Zr16O2$ isotope were determined to be $A=19881.352\pm 0.068MHz,B=7693.895\pm 0.021MHz$, and $C=5533.111\pm 0.036MHz$. The $r0$ structure was determined to possess a Zr-O bond length of $1.7710\pm 0.0007$ {\AA}, and an O-Zr-O bond angle of $108.11\pm 0.08\circ$. The electric dipole moment has been measured for the $\mathrm{<mrow\; data-mjx-texclass="ORD">90</mrow>}Zr16O2$ isotope and found to be $\mu b=7.80\pm 0.02$ Debye. The nuclear quadrupole hyperfine structure for the $\mathrm{<mrow\; data-mjx-texclass="ORD">91</mrow>}Zr16O2$ isotope has also been recorded and analyzed, yielding $\chi aa=115.94\pm 0.16MHz,\chi bb=-37.55\pm 0.33MHz$, and $\chi cc=-78.39\pm 0.16$ MHz. High-level density functional theory calculations have yielded a structure that agrees well with the values determined experimentally.