Organic versus Inorganic Molecules: Part II
In part I, we discussed an introduction to organic versus inorganic compounds. In part II, we dive a bit deeper into these concepts.
Organic pigments are composed of carbon-based molecules usually attached to a hydrogen. These molecules often contain conjugated systems of alternating single and double bonds, which can lead to extensive delocalization of electrons and give rise to the vibrant colors that are characteristic of organic pigments. As mentioned in part 1, the molecular structures of organic pigments are typically complex and can vary widely depending on the specific pigment.
Inorganic pigments are typically simpler compared to organic pigments, consisting of repeating units of metal atoms and non-metal atoms (e.g., oxygen).Inorganic pigments are composed of metal oxides, sulfides, or other inorganic compounds. The less vibrant color of inorganic pigments often arises from the interaction of metal ions with light, such as the absorption of certain wavelengths of light due to electronic transitions within the metal ions. Examples of inorganic pigments include titanium dioxide (white), iron oxides (red, yellow, brown), and chromium oxide (green), each with its own characteristic crystal structure and optical properties.
Generally speaking, inorganic pigments tend to be opaquer (more opaque) when compared to organic pigments. This opacity is often due to the larger particle size and denser structure of inorganic pigments. Due to this, inorganic pigments typically have solid coloration and provide excellent coverage when applied.
In summary:
Organic pigments are characterized by complex carbon-based molecular structures
Inorganic pigments are composed of simpler metal-containing compounds.
These differences in molecular structure contribute to the distinct properties and behaviors of organic and inorganic pigments, including their color, opacity, stability, and compatibility with different mediums.
Stay tuned for Part III in this three part series! In part III we take a deeper dive into opacity and transparency! You do not want to miss this one!