I know that chemical bonds can be divided into three categories, namely, ionic bonds, metallic bonds, and covalent bonds. During the molecular dynamics simulation of rocks, what's the chemical bonds between same minerals and difference minerals in rocks?
Molecular compounds are held together on an atomic level by chemical bonds. Three types of chemical bonds include ionic bonds, metallic bonds, and covalent bonds. The types of chemical bond influence the physical properties of the molecular compounds they form.
Molecular compounds held together by ionic bonds are salts. Salts readily precipitate from and dissolve in water. Natural salts like halite (NaCl) and gypsum (CaSO4) are soft minerals (not suitable for gems because they scratch or fracture easily, and can dissolve in water).
Metals are held together by metallic bonds. Compounds with metallic bonds transmit electricity. Metalloids are intermediate between those of metals and solid nonmetals. Although most elements are metals (all those on the left and center parts of the Periodic Table), only a few elements occur naturally in metallic form including gold, platinum, copper, iron, and mercury (in liquid form). Some minerals are metalloid compounds including pyrite (FeS2), magnetite(Fe3O4), and galena (PbS).
Molecular compounds held together by covalent bonds and are non-metallic compounds. These materials can form crystal complexes and do not transmit electricity and tend to be durable compounds. Most gems are non-metallic compounds. The mineral quartz (SiO2) is a non-metallic crystalline compound (see Figure 1-9).
cited from http://geologycafe.com/gems/chapter1.html
Here comes another question, since most minerals are non-metallic crystalline compounds held together by covalent bonds (and will not transmit electricity), why rocks still can transmit electricity? it's that because the existence of water and/or other filling materials?
Elements bond together to form minerals：
• Ionic bonds – balance of negative and positive charges of different ions (e.g., rock salt)
• Covalent bonds – sharing of electrons between elements (e.g., diamond) to achieve a stable atomic structure
cited from https://web.njit.edu/~taozhou/ccc/PPT_Ch07.pdf