Mn-based　metal　halides　scintillators　with　high　photoluminescence　quantum　yield　(PLQY)　have　recently　emerged　as　promising　large-size　candidates　for　X-ray　imaging　but　still　remains　as　difficult　challenge　in　stability　and　high　processing　temperatures.　Here,　three　manganese　halides　are　designed　by　introducing　branched　chains　into　organic　cations　and　extending　the　carbon　chains,　namely　(i-PrTPP)2MnBr4,　(i-BuTPP)2MnBr4　and　(i-AmTPP)2MnBr4,　successfully　lowered　the　melting　point　of　manganese　halides　to　120.2　degrees　C.　Three　materials　show　striking　light　yields　of　59　000,　40　000,　and　52　000　photons　MeV-1,　respectively.　The　lowest　detection　limits　are　42.30,　50.92,　and　45.71　nGy　s-1,　respectively.　Meanwhile,　compared　to　their　counterparts　with　linear　carbon　chains,　the　introduction　of　branched　chains　has　significantly　enhanced　the　stability　of　the　scintillators　in　the　glass　state.　A　transparent　glass　has　been　prepared　using　a　melt-quenching　method,　which　exhibited　80%　transmittance　at　400-700　nm.　The　glass　is　utilized　for　X-ray　imaging,　achieving　a　high　spatial　resolution　up　to　46.6　lp　mm-1.　This　result　provides　a　new　approach　to　enhancing　the　performance　of　such　scintillator　materials.