[2] Because selenopyrylium is a positively charged ion, it takes the solid form as a salt with non-nucleophillic anions such as perchlorate, tetrafluoroborate, fluorosulfate, and hexafluorophosphate.

The wavelength is longer than in thiopyrylium and pyrylium, but the intensity is weaker, due to selenium being less electronegative.

Band II, also called 1La, is stronger and longer than that of benzene, thiopyrylium and pyrylium.

[2] The nuclear magnetic resonance spectrum shows a 10.98 ppm shift for H2 and 6, 8.77 for H3 and H5 and 9.03 for H4 (BF4− salt dissolved in CD3CN).

[2] Solvents include trifluoroacetic acid, methanol, dichloromethane, chloroform, and acetonitrile.