Measure level gaps for atoms, photons, and spectra. Convert units and inspect related photon properties. Use the calculator below for clear physics problem solving.
| Lower Label | Upper Label | Lower Energy (eV) | Upper Energy (eV) | Absolute Gap (eV) | Frequency (Hz) | Wavelength (nm) | Transition |
|---|---|---|---|---|---|---|---|
| n = 1 | n = 2 | -13.600 | -3.40000 | 10.2000 | 2.46635e+15 | 121.553 | Absorption |
| n = 2 | n = 3 | -3.4000 | -1.51111 | 1.88889 | 4.56731e+14 | 656.387 | Absorption |
| Excited | Ground | -3.4000 | -13.6000 | 10.2000 | 2.46635e+15 | 121.553 | Emission |
| Band A | Band B | 0 | 2.50000 | 2.50000 | 6.04497e+14 | 495.937 | Absorption |
Signed energy difference: Delta E = E upper - E lower
Absolute gap: |Delta E| = absolute value of Delta E
Photon frequency: nu = |Delta E| / h
Photon wavelength: lambda = h c / |Delta E|
Wavenumber: wavenumber = 1 / lambda in cm^-1
Here, h is Planck's constant and c is the speed of light.
This energy difference between two energy levels calculator helps you measure the gap between two states. It works well for atomic physics, spectroscopy, quantum mechanics, and photon analysis. You can enter lower and upper energies in eV, joules, kJ/mol, or Hartree. The tool then converts the gap into useful forms. It reports the signed change, absolute energy gap, photon frequency, wavelength, wavenumber, and period.
Energy levels describe allowed states in many physical systems. Electrons in atoms occupy specific levels. Molecules also show quantized vibrational and rotational states. When a system moves between levels, it absorbs or emits energy. That energy often appears as a photon. The gap size controls the photon frequency and wavelength. A larger gap produces a higher frequency and a shorter wavelength. This relationship is central in spectroscopy and light emission studies.
The calculator is helpful when comparing ground states and excited states. It also supports negative energy values. Negative values are common in bound-state problems. The sign of the difference gives physical meaning. A positive signed difference means the upper level is higher. That case usually represents absorption. A negative signed difference means the system drops to a lower state. That case usually represents emission.
Many students first compute the energy gap. Then they must convert it again for frequency or wavelength. This page combines those steps in one place. It reduces mistakes in unit conversion. It also makes homework checking faster. Researchers can use it for quick estimates during model building, data review, or spectral peak interpretation. The example table gives reference values for common transitions and supports easier comparison.
The result section appears directly under the header after submission. That layout keeps the answer visible without extra scrolling. You can review the numerical output, export a CSV file, or create a PDF copy. This makes the calculator useful for lab notes, classroom practice, and technical reports. If the two levels are equal, the tool correctly shows a zero gap and no photon transition.
It is the gap between one allowed state and another. In physics, that gap determines how much energy must be absorbed or emitted during a transition.
The signed value shows direction. The absolute value shows the photon energy magnitude. Both are useful when interpreting absorption, emission, and level ordering.
Yes. Negative energies are common in bound systems, especially atomic models. The calculator handles them correctly and still computes the true gap.
It means the upper level is higher than the lower level. That usually indicates absorption is needed to move into the upper state.
Photon energy equals h times frequency. Because wavelength and frequency are related, a larger energy gap gives a shorter wavelength and higher frequency.
You can enter values in joules, electron volts, kilojoules per mole, or Hartree. The result section then shows several converted outputs automatically.
The energy difference becomes zero. In that case, there is no photon energy gap, so frequency and wavelength are not physically meaningful for a transition.
Yes. It is useful for spectroscopy, atomic transitions, emission lines, absorption studies, and quick checks of photon frequency or wavelength from a known gap.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.