High resolution vibration-rotation spectrum of the D2O molecule in the region near the 2 nu(1)+nu(2)+nu(3) absorption band

The high resolution Fourier transform spectrum of the D2O (nu = nu (1) + nu (2)/2 + nu (3) = 3.5) polyad was analysed within the framework of the Hami ltonian model taking into account resonance interactions between the seven states (310), (211), (112), (013), (230), (131) and (032). Transitions belo nging to the 2 nu (1) + nu (2) + nu (3), 3 nu (1) nu (2) and 3 nu (2) + 2 n u (3) bands were assigned in the experimentally recorded spectrum. This pro vided the possibility of obtaining spectroscopic parameters of the 'visible ' states (211), (310) and (032) and of estimating the band centres, and the rotational and resonance interaction parameters of the 'dark' states (112) and (131).