Convert cm^-1 to eV: Solve with Solution

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In summary, in optical spectroscopy, the unit cm^-1 is commonly used to define the energy or frequency of a photon in a transition between electronic states of an atom. This is derived from the reciprocal of the wavelength of the photon in cm. The conversion factor from cm^-1 to eV can be determined by using the equation E=hc/lambda, where h and c are constants. The solution to this problem can be used to complete the rest of the problem.
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Fowler_NottinghamUni
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Apparently In optical spectroscopy it is common to use the unit cm^-1 tro define the energy (or frequency of a photon that is emitted or absorbed in a transition between electronic states of an atom. This is derived from the reciprocal of the wavelength of the photon (wavelength in cm). Determine the conversion factor that converts cm^-1 to eV. I have no idea how to do this in the problem sheet that he gave us the solution to this particular problem means that we can use the result to complete the rest of the problem. :smile:
 
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E=hc/lambda. plug in the constants and see what's the energy of a 1cm wavelength photon. I don't think there's really anything more to it.
 
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The conversion factor to convert cm^-1 to eV is 1 cm^-1 = 0.00012398 eV. This can be derived from the relationship between energy and wavelength, where energy is equal to Planck's constant (h) times the speed of light (c) divided by the wavelength. In this case, we can use the fact that the wavelength is in cm and the energy is in eV to determine the conversion factor.

First, we need to convert the wavelength from cm to meters, as the speed of light is typically given in meters per second. This can be done by multiplying the wavelength in cm by 0.01 (since there are 100 cm in 1 meter).

Next, we can rearrange the equation to solve for energy, which gives us energy = (h*c)/wavelength. Plugging in the values for Planck's constant (6.626 x 10^-34 J*s) and the speed of light (3.00 x 10^8 m/s), we get energy = (6.626 x 10^-34 J*s * 3.00 x 10^8 m/s)/wavelength.

Since we want the energy in eV, we can divide the energy by the conversion factor for Joules to eV, which is 6.24 x 10^18. This gives us energy = (6.626 x 10^-34 J*s * 3.00 x 10^8 m/s)/wavelength * (1 eV/6.24 x 10^18 J). Simplifying this, we get energy = 1.06 x 10^-5/wavelength eV.

Finally, to convert from cm^-1 to eV, we need to take the reciprocal of the wavelength (since cm^-1 is the reciprocal of wavelength in cm). This gives us the conversion factor of 1 cm^-1 = 1/wavelength eV. Plugging in the value for wavelength (in meters), we get 1 cm^-1 = 1/(wavelength in cm * 0.01) eV. Simplifying this, we get 1 cm^-1 = 0.00012398 eV.

Therefore, to convert from cm^-1 to eV, we simply need to multiply the value in cm^-1 by 0.00012398. For example, if we have a value of 500 cm
 

FAQ: Convert cm^-1 to eV: Solve with Solution

1. How do I convert cm^-1 to eV?

To convert from cm^-1 to eV, you can use the formula: 1 cm^-1 = 1.2398 x 10^-4 eV. This means that to convert a value in cm^-1 to eV, you need to multiply it by 1.2398 x 10^-4.

2. Can you show an example of converting cm^-1 to eV?

Sure, let's say we have a value of 500 cm^-1. To convert this to eV, we would multiply it by 1.2398 x 10^-4. This gives us 0.062 eV.

3. Why do we need to convert cm^-1 to eV?

cm^-1 (inverse centimeters) is a unit commonly used in spectroscopy to measure the energy of light. However, eV (electron volts) is a more commonly used unit to measure energy in other scientific fields. Therefore, it may be necessary to convert between the two units for comparison or to use in calculations.

4. Is there an online converter for cm^-1 to eV?

Yes, there are many online converters that can easily convert between cm^-1 and eV. Simply search for "cm^-1 to eV converter" and you will find multiple options.

5. What is the relationship between cm^-1 and eV?

The relationship between cm^-1 and eV is an inverse one. This means that as one unit increases, the other unit decreases. In other words, as energy increases in eV, the corresponding value in cm^-1 decreases.

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