Importantly, the regular cavities of the water lattice can accommodate gas molecules and create gasbearing structures -gas hydrates (Fig ). Gas such as hydrogen, methane and carbon dioxide can incorporate in the water lattice up to a mass fraction of ~5%, 15% and 30%, respectively. Gas hydrates containing hydrogen or methane are energy carriers, commonly referred to as combustible ice, frozen energy, powdered H 2 or powdered methane. of small spherical solutes scales with their volume, whereas for large solutes, G hyd is determined by interfacial physics and scales with solute area, A; the crossover between the two regimes occurs at a solute size of roughly 1 nm. Furthermore, small solute hydration is entropically unfavorable, so G hyd increases as temperature is increased from T low (blue) to T high (red ); in contrast, for large solutes, G hyd decreases as temperature is increased. Part (a-b) is reproduced with permission from Bandyopadhyay et al. Part (c-e) is reproduced with permission from Rego et al. Flexible H-bonds and Adaptable Water Lattice: The geometric constraints in Figure underpin the unique features of the hydrogen bonding and make the H-bonding distinct from other types of binding and interaction. First, the angular constraint (𝛽) defines the directional characteristic of the H-bonding, which makes H-bonding differ in nature from non-directional interactions such as electrostatic and van der Waals (vdW) forces. H-bonding is constituted by both directionality (covalence, weighing ~10% of the H-bond) and non-directionality such as electrostatic and van der Waals (vdW) forces, weighing ~90% of the H-bond. The weak covalence characteristic of the H-bonding plays integral roles in the anomalous properties of water structures. The weak covalence character is sufficient to sustain the crystallinity and orderliness of the water network. That's why the water network (i.e. ordinary ice) is crystalline whereas wdW-based materials such as solid CO 2 are amorphous. Interestingly, this partial covalency enables the flexibility of H-bonds and water lattice, in contrast to the rigidity of typical covalent crystals such as diamonds or quartz. The length (𝑟 OO ) and angle (𝛽) can vary within a window (Fig ) without causing a rupture of the H-bond. The binding energy of individual H-bonds can vary between 1 kcal. mol -1 and 15 kcal. mol -1 (ref. ). This flexibility nature of H-bonds with respect to the geometric constraints and bonding energy empowers the water network to adapt to prevailing conditions. Water network is neither rigid like covalent crystals nor disordered like vdW-based solids.