Knowledge Bank

The microwave spectra of three isotopic species of methoxyamine ($CH3$O$NH2$) have been studied. For the normal species the ground-state rotational constants are A = 42 488 $\pm$ 150 MHz, B = 10 049.59 $\pm$ 0.03 MHz, and C = 8962.85 $\pm$ 0.03 MHz. From these data and those from the -NHD and -$ND2$ species, the amino protons have been shown to occupy a symmetrical trans position relative to the methyl group. The barrier to internal rotation of the methyl group has been found to be 873 $\pm$ $15cm-1$ by analysis of ground state splittings. Analysis of hyperfine splittings has yielded the $\mathrm{<mrow\; data-mjx-texclass="ORD">14</mrow>}N$ quodrupole coupling constants, which have the following values for the normal isotopic species: $\chi aa$ = 3.63 $\pm$ 0.03 MHz, $\chi bb$ = - 3.69 $\pm$ 0.07 MHz and $\chi cc$= 0.06 $\pm$ 0.07 MHz.