Wavenumber and Energy in IR

[NonTraditional3]

Cannot figure this out - used to know it pretty well, went back to confirm, and I completely forgot the relationship here.

If wavenumber is inverse of wavelength, inverse of wavelength corresponds directly to energy. So, what is considered higher energy? A wavenumber of 3200-3600 cm^-1, or 1700cm^-1?

If higher wavenumber is more energy, would that mean since it's an inverse relationship (cm^-1) that 400^-1, being equivalent to 1/4000, is less energy than 1700cm^-1?

Someone please provide their insights on this, thank you!

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[circulus vitios]

Greater wave number (units in reciprocal length), greater energy.

http://orgchem.colorado.edu/Spectroscopy/irtutor/IRtheory.pdf (Top of page 156)
http://orgchem.colorado.edu/Spectroscopy/Spectroscopy.html

 

[richkaj]

You can interconvert between wavelength and wavenumber by doing the reciprocal of each. i.e. 400 nm = (400 x 10^-7 cm)^-1 = 25,000 cm^-1. Hope this helps... The longer the wavelength the less energy it has, given that the wavelength is inversely proportional to E. Hope this helps...