Au-0 atoms were produced via the electron capture of Au+ ions in gamma-irradiated solid solutions of MTHF at 77 K. The optical absorption bands observed in the regions of UV and NUV are ascribed to Au-0. The steady-state emission and excitation spectra were measured by photoexcitation at 73 K before and after gamma-irradiation of the solid solutions containing [Au+] ions. The two-dimensional time-resolved emission spectra were also investigated by photoexcitation at lambda(exc) = 337, 380, and 420 nm by using an N-2 laser and dye lasers. A set of five emission bands of 385, 430, 480, 520, and 580 nm and another set of emission bands at 456, 482, 484, and 520 nm were observed. The latter set of emission bands showed such characteristic structures as the mirror image of the absorption bands of Au-0 in the rare gas matrixes. The emission band at 430 nm observed before gamma-irradiation was confirmed to be phosphorescence due to Au+ with a lifetime of about 625 ms. A part of the emission band of 385 nm observed after gamma-irradiation was also due to phosphorescence consisting of two components with lifetimes of 146 and 461 ms. Three types of exciplexes (Au+.Ln)*, (Au-0.Ln...Au+)*, (Au-0.Ln)*, and the excited gold atom (Au-0)* are proposed for all the emission bands including phosphorescence. The excited gold atoms in 2P(1/2) and 2P(3/2) states participate mainly in the formation of these emissive exciplexes. The formation mechanism for these species is also presented.