# Reflectivity of metals and elements

• mdergance3
In summary, calculating reflectivity of different wavelengths of light based off of physical properties is not as straightforward as one might think.

#### mdergance3

Hello all,
I was wondering if there was a way to calculate the reflectivity of differing wavelengths of light hitting an element based upon its physical properties. I know that it is based on how the atoms of the material are excited based upon the wavelength hitting it. I eventually want to determine what wavelengths will reflect off of a specific metal in a pile of other stuff in order to locate said metal.
Any help will be appreciated,
Thank you

if the atom were excited then the light would be absorbed.

mdergance3 said:
Hello all,
I was wondering if there was a way to calculate the reflectivity of differing wavelengths of light hitting an element based upon its physical properties. I know that it is based on how the atoms of the material are excited based upon the wavelength hitting it. I eventually want to determine what wavelengths will reflect off of a specific metal in a pile of other stuff in order to locate said metal.
Any help will be appreciated,
Thank you

Metals and atoms are two entirely different beasts. In fact, solids and atoms are two entirely different beasts. If they are the same, then atomic-molecular physics would be identical to Solid State Physics, and having two separate field of studies would be redundant.

Zz.

So does that mean there isn't a way to calculate what wavelengths of light will reflect off of a metal and that it can only be done experimentally?

mdergance3 said:
So does that mean there isn't a way to calculate what wavelengths of light will reflect off of a metal and that it can only be done experimentally?

It can be calculated by "anyone" for an idealized metal (which is what Granpa is linking to). However, for real metals you need some pretty sophisticated computer models to even get started.
It also depends on what you mean by "light"; visible light covers only a small part of the spectrum; much of the interesting stuff goes on at other wavelengths (e.g. in the IR part of the spectrum).
What you describe is a form of spectroscopy, and my guess is that the visible part of the spectrum is not the best choice for differentiating between different metals.

mdergance3 said:
Hello all,
I was wondering if there was a way to calculate the reflectivity of differing wavelengths of light hitting an element based upon its physical properties. I know that it is based on how the atoms of the material are excited based upon the wavelength hitting it. I eventually want to determine what wavelengths will reflect off of a specific metal in a pile of other stuff in order to locate said metal.
Any help will be appreciated,
Thank you

Would you want to identify just elemental metals, or all metals including the many varieties of alloys used to manufacture goods?

Also, reflectivity of a metal can change over time as an oxide layer slowly forms on its surface. Reflectivity will also depend on the degree of surface smoothness/roughness.

There are many variable factors to consider here.

## 1. What is the relationship between reflectivity and the type of metal or element?

The reflectivity of a metal or element is dependent on the properties of the material such as its atomic structure and surface texture. Some metals, like silver and aluminum, have a higher reflectivity compared to others.

## 2. How is the reflectivity of a metal or element measured?

The reflectivity of a metal or element is typically measured using a spectrophotometer, which measures the amount of light reflected off the surface of the material. The results are usually given as a percentage, with 100% being perfect reflectivity.

## 3. Can the reflectivity of a metal or element be affected by external factors?

Yes, the reflectivity of a metal or element can be affected by external factors such as temperature, humidity, and surface contamination. These factors can alter the surface texture and affect the angle at which light is reflected, resulting in a change in reflectivity.

## 4. How does the thickness of a metal or element affect its reflectivity?

The thickness of a metal or element can affect its reflectivity by changing the angle at which light is reflected. Thicker materials tend to have a lower reflectivity, as the light has a longer distance to travel and may be absorbed or scattered before it is reflected.

## 5. What are some real-world applications of reflectivity of metals and elements?

The reflectivity of metals and elements has many practical applications. For example, highly reflective materials are used in solar panels to efficiently capture and convert sunlight into energy. Reflective coatings are also used in mirrors, headlights, and telescopes. In addition, the reflectivity of metals is important in the manufacturing of reflective clothing, building materials, and food packaging.