Hi, I got the complex conductivity vs. frequency table of a metamaterial. Its first lines are like this: f conductivity 1GHz 0.004+0.00297i 1.1GHz 0.004+0.00295i 1.2GHz 0.003+0.00294i the table goes up to 10GHz. Now the problem is that I need to enter this material into electromagnetic simulation tools. But these tools require a real permittivity and frequency dependent loss tangent (CST and HFSS). So how can I calculate complex permittivity (real permittivity and loss tangent) from the above data? Thanks in advance.