The unique and tunable optical properties of nanoparticles are a key driver for their utility across applications in diagnostics, nanomedicine, and advanced optical systems.
The nanoComposix Mie Theory calculator estimates the optical cross-sections of single-component and core-shell spherical nanoparticles, showing how composition, particle size, shell thickness, and surrounding refractive index influence extinction, absorption, and scattering.
What can you do with this calculator?
Use the calculator to compare how particle size, shell structure, surrounding medium, and wavelength range influence nanoparticle extinction, absorption, and scattering.
Size-dependent spectra
Compare how nanoparticle size changes the calculated extinction spectrum across your selected wavelength range.
Absorption vs. scattering
Identify whether absorption or scattering dominates, and how each contributes to total extinction for a given particle design.
Core-shell particle design
Explore how shell thickness and shell material influence optical cross-sections, spectral position, and local refractive index effects.
Formulation effects
Adjust the surrounding refractive index to approximate buffers, polymer matrices, biological media, coatings, or resins.
Example spectra (calculated)
Gold Nanospheres vs. Gold Nanoshells
Compare how a core-shell geometry changes the calculated optical response relative to a solid gold sphere.
Size Dependence of Titanium Dioxide
Compare how titania diameter affects spectral intensity, activity within the UV region, and the balance between absorption and scattering.
Media Dependence of Aluminum Nanoparticles
Compare how changing the surrounding refractive index shifts the calculated optical response.
Size Dependence of Gold Nanospheres
Compare how gold nanosphere diameter affects spectral intensity and the balance between absorption and scattering.
Size Dependence of Silver Nanospheres
Compare how silver nanosphere diameter changes peak shape, intensity, and absorption/scattering contributions.
Mie theory calculator instructions
Select a Core material from the dropdown menu and enter the diameter in nanometers. If Other is chosen for the Core Type, enter the refractive index (RI) in the box. Note that this is the real refractive index only, with no absorption component.
Note: Diameter strongly affects whether optical extinction is dominated by absorption or scattering. Try comparing small and large particles to see how the balance changes.
If a Shell material is to be included, select the material and enter the thickness of shell in nanometers, or choose None if no shell is needed.
Note: Core-shell models are useful for exploring coatings, stabilizing shells, nanoshell architectures, and surface modifications that change the local optical environment.
Enter the starting and ending wavelengths of the spectral range to be calculated, and enter the refractive index of the media surrounding the particles. Press “Plot!” to calculate the extinction, absorption, and scattering cross sections for a single particle. A csv file of the data can be downloaded; note that the cross-section units in the downloaded data are in units of m2/particle.
Note: Calculating optical response in variable media such as buffers, polymer matrices, biological media, coatings, or resins is useful for nanoparticle-enabled technologies across diagnostic, nanomedicine, and optical engineering applications.
How to cite the nanoComposix Mie theory calculator
The Mie theory implementation used here was developed by Steve Oldenburg, Founder of nanoComposix, as part of his doctoral work at Rice University. More details on theory and code can be found in his dissertation, which can be cited as Oldenburg, S. J. Light Scattering from Gold Nanoshells. Diss. Rice University, 2000.
Materials commonly modeled with Mie theory
This calculator is designed for spherical single-component and core-shell particles. Use it to compare optical behavior across material classes, then explore which nanoComposix materials might be right for your application!
Gold Nanospheres
Compare size- and media-dependent extinction for gold spheres.
Silver Nanospheres
Model how silver sphere diameter influences peak position, broadening, absorption, and scattering.
Gold Nanoshells
Explore how silica core diameter and gold shell thickness tune absorption and scattering.
Silica-Shelled Nanospheres
Compare how a dielectric shell alters the calculated response of a plasmonic core.
Silica & Titania
Evaluate size-dependent scattering and absorbance of dielectric particles.
Custom Nanoparticles
Tailor particle size and composition for your specialized optical requirements.
Note: Anisotropic nanomaterials such as gold nanorods and silver nanocubes are not directly modeled by this spherical Mie theory calculator. Contact us with any questions about how these materials may work for your application.
Explore nanoparticle platforms by application
Optical cross-sections are just one part of nanoparticle design. Learn more about how nanomaterials are applied across application areas, and which may be the right fit for your project.
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Material property references
Dielectric values in the calculator are taken from literature, and multiple sources may be used for a given material to extend the range of wavelengths that can be used for calculations. The CRC Handbook of Chemistry and Physics and the RefractiveIndex.info website are useful references that provide information and literature sources describing the optical properties of a wide range of materials.