The vibrational-rotational high-resolution spectrum in the region of 3$\nu_4$, $\nu_2$ + 2$\nu_4$ and 2$\nu_2$ + $\nu_4$ bands of the $^{72}$GeH$_4$ molecule

The high-resolution spectrum of the $^{72}$GeH$_4$ molecule was recorded on a Bruker IFS 125HR Fourier spectrometer with an optical resolution of 0.003 cm$^{-1}$. The line positions were analyzed for ten interacting vibrational-rotational bands 3$\nu_4$ (1$F_2$, $F_1$, 2$F_2$), $\nu_2$ + 2$\nu_4$ (1$E$, $F_1$, $F_2$, 2$E$) and 2$\nu_2$ + $\nu_4$ (1$F_2$, $F_1$, 2$F_2$) in the range 2350–2750 cm$^{-1}$. As a result of the analysis, 1726 experimental lines were identified with the maximum value of the quantum number J$^{\mathrm{max}}$ = 17; then used in the fitting procedure with parameters of the effective Hamiltonian. The resulting set of 35 spectroscopic parameters describes the vibrational-rotational structure of the spectrum with $d_{\mathrm{rms}}$ = 7.5 $\cdot$ 10$^{-4}$ cm$^{-1}$.