The inorganic solid formed between lithium Li and fluorine F is lithium fluoride LiF . This compound is an ionic solid, which is characterized by the following features:1. Crystal lattice structure: Ionic solids have a regular arrangement of ions in a crystal lattice structure. In the case of lithium fluoride, it has a face-centered cubic lattice structure.2. High melting and boiling points: Ionic solids generally have high melting and boiling points due to the strong electrostatic forces between the positively charged cations Li+ and negatively charged anions F- . Lithium fluoride has a melting point of 845C 1553F and a boiling point of 1676C 3050F .3. Electrical conductivity: Ionic solids do not conduct electricity in their solid state because the ions are held in fixed positions within the crystal lattice. However, when dissolved in water or melted, they can conduct electricity as the ions become free to move.4. Solubility: Ionic solids tend to be soluble in polar solvents like water, which can break the ionic bonds and surround the individual ions. Lithium fluoride is moderately soluble in water.5. Hardness and brittleness: Ionic solids are generally hard and brittle due to the strong ionic bonds holding the crystal lattice together. When force is applied, the lattice can break along planes, causing the material to fracture.