Three-pole Debye model parameters of soil dielectric permittivity spectra

The dataset contains fitted three-pole Debye dielectric model parameters of 567 soil spectra. Three soils of loamy sand, sandy loam, and silt loam textures were tested. Of each soil, 20 samples of various water contents were prepared with the use of distilled water and potassium chloride solutions, 5 samples for each liquid. Air-dry samples were also prepared. Dielectric spectra were obtained with the use of a six-channel coaxial-transmission-line cell system at 9 controlled temperature steps from 0.5 to 40°C in the 0.02 – 3 GHz frequency range.

To each obtained spectrum, the three-pole Debye model with an added DC electrical conductivity term was fitted with the use of a procedure utilizing the Levenberg-Marquardt nonlinear least squares algorithm. The dataset contains model parameters with their standard errors and RMSE. Parameters of the samples: volumetric water content, temperature, electrical conductivity of the solutions, soil textures, and the formula for the dielectric model were included in the dataset file.