简介：ThevalencechangesofdopedsamariumandthecreationaswellastheannihilationofF-centersintheprocessesofthermostimulatedluminescence（TSL）andphotostimulatedluminescence（PSL）ofBaFCl∶Smcrystalhavebeenstudied.AsbeingirradiatedbyX-ray,alargenumberofelectron-holepairsarecreatedinthecrystal.Mostoftheelectronsmaybetrappedattheanionvacancies,producingF-centers.Thedopedsamariumions,whichexistedmostlyintrivalentstate(Sm3+),maycapturetheholesandconvertthemselvestotetravalentstate.SothatpartoftheincidentX-rayenergyarestoredinthisnonequilibriumsystem.Onopticalandthermalstimulationthestoredenergycanbeliberatedasacharacteristicemissionoftrivalentsamariumion.ThisemissionoriginatesfromtherecombinationoftheF-centerelectronswithtetravalentsamariumions,i.e.theF-centerelectronsmaybeexcitedtotheconductionbandbyopticalorthermalstirnulationandthenrecombinewithtetravalentsamariumions.ThisrecombinationmakesthesamariumionstobeinsitureducedtotheexcitedstateofSm3+,andgivesrisetothecharacteristicemissionofSm3+.Ontheotherhand,duringX-irradiationafewelectronscanbetrappedatthesitesoftrivalentsamariumionsandreducethemtodivalentstate.ButtheformationofdivalentsamariumOnX-irradiationisverysmallascomparedwiththatofF-centersandsotheirinfluenceonthePSLandTSLcanbeneglected.

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简介：Awhitelong-lastingphosphorCa2MgSi2O7:Dy3+waspreparedbythesolid-statereaction.Astrongbandpeakedat260nmwasshownintheexcitationspectrumof578nmemission,whichmightbeattributedtotheoxygendeficiencyofthehost.Afterirradiatedwith254nmfor4min,thewhiteafterglowofthesamplecouldbeseenfor3h.Moreover,thedepthsandfrequencyfactorsoftrapcenterswerecal-culatedfromthethermo-luminescencecurveofthesample,whichindicatedthatthetrapcenterscorrespondingtothe414Kbandweremorehelpfultothelong-lastingphosphorescence.