Lanthanide　ions　doped　tetragonal　LiYF4　has　became　an　investigative　focus　of　upconversion　luminescence　(UCL)　materials　for　its　well　properties　of　multi-photon　UCL　and　as　a　comparable　matrix　material　with　hexagonal　NaYF4.　While　the　cause　for　its　well　performance　on　short　bands　emission　is　still　unrevealed.　After　the　exploration　of　crystal　structure　characteristic　of　tetragonal　LiYF4,　a　hexagonal　circle　sublattice　structure　of　Y3+　with　0.3710　nm　interval　between　adjacent　Y3+　ions　and　larger　than　0.5　nm　interval　between　meta-position　and　para-position　Y3+　ions　were　revealed.　The　energy　transfer　of　rare　earth　ions　are　easy　take　place　around　the　hexagonal　circles　or　among　the　cluster　of　five　adjacent　trivalent　ions.　Base　on　the　sublattice　structure　characteristic　of　tetragonal　LiYF4,　we　have　an　idea　to　study　UCL　mechanism　systematically　of　tetragonal　LiYF4:RE　by　the　construction　of　sublattice　energy　cluster　1M-xYb　(M=Er,　Ho,　Tm)　and　the　manipulation　of　crystal　field　symmetry　by　introducing　different　amount　Yb3+　ions　and　Sc3+　or　Hf4+　ions,　respectively.　Hydrothermal　method　was　employed　to　prepare　LiY0.98-xYbxEr0.02F4,　LiY0.98-xYbxHo0.02F4,　LiY0.995-xYbxTm0.005F4,　LiY0.68-xYb0.3Er0.02ScxF4　and　LiY0.68-xYb0.3Er0.02HfxF4　series　samples.　A　typical　preparation　process　demonstrate　as　follows,　at　first,　(1-x)　mmol　Y(NO3)3　(0.2　mol/L),　x　mmol　(x=0.2,　0.5,　0.7　and　0.9)　Yb(NO3)3　(0.20　mol/L)　and　Er(NO3)3　(0.02　mmol)　solution　was　dropwise　added　into　20　mL　deionized　(DI)　water　with　1　mmol　EDTA　to　form　a　solution　under　vigorous　stirring　for　30　min.　Secondly,　3.0　mL　LiOH　(1.0　mol/L)　and　4.0　mL　NH4HF2(1.0　mol/L)　aqueous　solution　were　dropwise　added　to　the　solution　under　thorough　stirring　for　30　min　until　the　solution　completely　became　a　white　emulsion,　the　pH　value　of　the　emulsion　is　3~4.　Finally,　the　white　emulsion　was　slowly　transferred　into　a　50　mL　Teflon-lined　autoclave,　sealed　and　heated　at　190℃　for　18　h.　The　final　products　were　collected　by　centrifugation,　and　then　washed　with　DI　water　several　times.　The　collected　samples　were　dried　at　60℃　over　night.　X-ray　powder　diffraction　(XRD)　and　Rietveld　refinement　method　were　employed　to　reveal　the　variation　of　crystal　structure,　field　emission　scanning　electron　microscopy　(FESEM)　and　field　emission　transmission　electron　microscopy　(FETEM)　were　employed　to　the　analysis　of　crystal　morphology　and　crystal　structure.　UCL　performance　was　analyzed　by　Edinburgh　fluorescence　spectrophotometer　FSP920.　After　investigation,　we　found　excited　energy　levels　distribution　of　different　RE　ions　is　diverse,　and　the　level　matching　with　Yb3+　are　different　too,　it　result　in　different　luminescence　quenching　of　energy　cross　relaxation,　so　the　different　sublattice　energy　clusters　1Er-2Yb,　1Ho-2Yb　and　1Tm-4Yb　of　different　active　rare　earth　ions　can　be　constructed　for　the　best　UCL　performance.　The　cystal　field　symmetry　of　tetragonal　LiYF4:Yb/Er　were　manipulated　successfully　by　6　mol%　Sc3+　or　4　mol%　Hf4+　doping,　and　UCL　intensity　were　enhanced　about　50%　with　6　mol%　Sc3+,　while　the　UCL　intensity　were　weaken　after　Hf4+　doping.　After　Sc3+　or　Hf4+　doping,　there　are　only　three　Yb3+　ions　in　the　five　trivalence　ions　cluster　that　can＇t　realize　two-photon　cooperation　upconversion　synchronous　electron　population　of　4F5/2　excited　state　level　of　Er3+　ions　and　2G7/2　or　4F5/2o　excited　state　level　of　Sc3+　or　Hf4+　respevticely,　and　then　Sc3+　and　Hf4+　ions　become　a　quenching　center　in　the　asymmetric　crystal　field　that　is　conversed　with　them　doped　hexagonal　NaYF4:Yb/Er　that　Sc3+　and　Hf4+　ions　were　taken　as　energy　storage　ions　and　dramatically　enhanced　UCL　performance.　In　this　work,　the　UCL　mechanism　of　sublattice　energy　cluster　construction　and　crystal　field　manipulation　were　revealed　that　may　be　an　inspiration　for　high　efficient　UC　luminescence　materials　design　and　preparation.　©　2020　Shanghai　Institute　of　Organic　Chemistry,　Chinese　Academy　of　Sciences.