(N/A) Metallic hydrides,also known as interstitial hydrides,are formed by many $d$-block and $f$-block elements.
These hydrides are often non-stoichiometric,meaning they are deficient in hydrogen (e.g.,$LaH_{2.87}, TiH_{1.5-1.8}, PdH_{0.6-0.8}$).
In these structures,hydrogen atoms occupy the interstitial sites within the metal lattice.
Certain transition metals,particularly $Pd$ and $Pt$,possess the unique ability to absorb and accommodate a very large volume of hydrogen gas.
Because of this high absorption capacity,these metallic hydrides can serve as efficient storage media for hydrogen,acting as a potential source of energy for future applications.