Why is ruby red and emerald green? These colors come from the same metal with the atomic structure

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Ruby and emerald colors are very impressive, so they define red and green colors, red and emerald green. But have you ever wondered how they would do those colors?
I am an inorganic chemist. Researchers in my field work to understand the chemistry of all elements that make up the periodic table. Many inorganic chemists are focusing on transition metals, that is, central elements in the periodic table. Transition metals contain most of the familiar metals such as iron (FE) and gold (au).
One of the characteristics of compounds made of transition metals is their strong colors. There are many examples, such as jewelry and paint pigments. Even the color of the blood is derived from protein hemoglobin containing iron.
Investigating the color of the compound containing transition metals will lead to truly amazing science.
Ruby and emerald are a wonderful example of how small transition metals (in this case, chromium) can create beautiful colors that are quite boring minerals.
Minerals and crystals
Both ruby and emeralds are minerals and are a type of rock with consistent chemical composition and highly ordered structure at the atomic level.
When the highly ordered structure is extended to all three -dimensional structure, the mineral becomes a crystal.
The theory developed by a physicist called Crystal Field theory in the 1920s can explain the reasons why Ruby and emeralds have the colors they do. The Crystal Field theory predicts how the structure of the transition metal ion is affected by other atoms surrounding it.
Ruby is mainly composed of mineral colandam, which is composed of elemental aluminum and oxygen in the normal repeated sequence. Each aluminum ion is surrounded by six oxygen ions.
Emerald is mainly composed of mineral beryl and is made from beryllium, aluminum, silicon, and oxygen elements. The crystal structure of the beryl is more complicated than the structure of the colandam for additional elements in the formula, but each aluminum ion is surrounded by six oxygen ions again.
Pure Candom and beryl are colorless. The vivid colors of ruby and emerald come from the existence of very small chrome. Chromium replaces about 1 % of the crandam or beryl clistal aluminum when ruby or emerald is formed underground at high temperatures and pressure.
But how can one element (cromium) create emerald ruby and green red color?
Color science
Ruby and emerald have colors, like many substances, to absorb some light of color. Like sunlight, the most visible light is composed of all the colors of the rainbow: red, orange, yellow, green, blue, indigo, violet. These colors make up a visible light spectrum. This is easy to remember as a Roy G BIV.
One of the main reasons for objects is to absorb one or more of these visible light. For example, when a substance absorbs red light, it means that red light is trapped in a substance and other colors reflect on your eyes. The color you see is the total of the remaining light, from the green to blue. When the substance absorbs blue, it looks red or orange to you.
Unlike colorless aluminum ions, chrome ion absorbs blue and green light when surrounded by oxygen ions. Because the red light is reflected, it is found in ruby.
In emerald, chromium is surrounded by six oxygen ions, but has a weaker interaction between chrome and surrounding oxygen ions. This is because beryl crystals have silicon and beryllium. They absorb blue light and red light in the emerald, leaving green to see you.
The ability to adjust the characteristics of transition metals like chrome by changing the surrounding things is my core strategy in my field of inorganic chemistry. By doing so, scientists can help understand the design of the compound for the basic science of metal -containing compounds and the specific purpose.
You can feel joy in the amazing colors of jewelry, but through chemistry, you can see how nature creates these colors using the infinite diverse structure created in the elements of the periodic table. You can.
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