(　)A　new　solid　solution,　Ba5.47Sr0.53Al4B14O33,　has　been　synthesized　by　a　high-temperature　solution　reaction　at　770　degrees　C.　The　compound　crystallizes　in　the　space　group　P1　with　a=　6.86873　(13)　angstrom,　b　=6.96992　(13)　angstrom,　c=　14.5370　(3)　angstrom,　alpha　=88.8075　(15)degrees,　beta=86.5809(15)degrees,　gamma=83.2613　(14)degrees,　V=　689.84　(2)　angstrom(3),　and　Z=1.　It　features　a　three-dimensional　(3D)　[Al-4(B6O14)　(B6O13)(BO3)(2)](n)(12n-)　framework　with　intersecting　channels　occupied　by　Ba2+　and　(Ba/Sr)(2+)　cations.　The　framework　is　constructed　by　1D　IAl2(B6O14)(B6O13)(BO3)(2)](n)(18n-　)chains　and　1D　IAl2O7](n)(18n-)　chains　interconnected　via　B-O-Al　bridges.　The　compound　melts　incongruently　at　844　degrees　C.　The　existence　of　BO3　and　BO4　groups　in　the　structure　was　indicated　by　vibrational　spectroscopy.　A　high　degree　of　transparency　in　the　visible　wavelength　range　and　a　band　gap　of　3.37　eV　were　revealed　by　UV-VIS　diffuse　reflectance　spectra.　The　band　structure　and　bonding　properties　have　been　investigated　and　the　insulating　nature　with　a　direct　energy　gap　was　confirmed.　[GRAPHICS]　.