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Since the initial assessment four decades ago of zirconium diberyllide, ZrBe₂, as a potential hydride-forming intermetallic for hydrogen-storage applications, structural and dynamical studies to date have been chiefly limited to the hydride composition, ZrBe₂H_1.5, which exists as a single-phase disordered hydride with hexagonal <i>P</i>6/<i>mmm</i> symmetry that undergoes hydrogen sublattice ordering below ~200 K (~235–250 K for ZrBe₂D_1.5). It is desirable from both fundamental and technological viewpoints to have a more complete understanding of the ZrBe₂H<i>_x</i> phase diagram. In the present study, both neutron powder diffraction and neutron vibrational spectroscopy measurements of ZrBe₂H<i>_x</i> at lower hydrogen contents (<i>x</i> < 1.5) indicate that at least two other ordered phases exist at low temperatures, coinciding with respective nominal <i>x</i> values of 1 and 0.67. Compared to ZrBe₂H_1.5, these more-hydrogen-dilute phases possess different structural symmetries (orthorhombic) with different H-sublattice orderings and undergo much-higher-temperature order-disorder transitions at ≈ 460 K (<i>x</i> = 1) and ≈ 490 K (<i>x</i> = 0.67) to the characteristic H-disordered hexagonal <i>P</i>6/<i>mmm</i> structure associated with ZrBe₂H_1.5.