The structure can thus be described as SiO 4 tetrahedra and non-Si-bonded O atoms surrounded by four Lu atoms in a distorted tetrahedron. Infinite chains of edge-sharing OLu 4 tetrahedra run along the c axis. The structure of Lu 2SiO 5 is shown in Fig. This was performed at the medium-flux R2 steady-state reactor at Studsvik, Sweden. Because of the poor accuracy achieved for the positional parameters of the O atoms, it was also decided to collect a single-crystal neutron diffraction data set. Structural information on the title material is therefore essential.Ī single-crystal X-ray data set was collected on a Siemens CCD diffractometer and the structure was solved using direct methods. embedded cluster calculations in a Hartree–Fock approach or periodic band structure calculations using a full-potential linear muffin tin orbital approach. This is being performed mainly through electronic structure calculations, i.e. It is necessary to understand the underlying scintillation mechanisms in order to develop even better scintillator materials for use in medical imaging, nuclear physics, high-energy physics and astrophysics. It is anticipated that the use of LSO in medical imaging will increase steadily in the foreseeable future. This corporation has now constructed the first LSO positron tomograph, which contains over 120 000 2.1 × 2.1 × 7.5 mm LSO crystals. This crystal is now being grown in large quantities by CTI Positron Systems Inc., Knoxville, Tennessee, USA, one of the largest producers of positron tomographs worldwide. More recently, the scintillation crystal Lu 2SiO 5:Ce (LSO Melcher & Schweitzer, 1992 ) was found to have a similar detection efficiency to BGO whilst being seven times faster and having a four times higher light output. Since 1980, the scintillation crystal Bi 4Ge 3O 12 (BGO) has been used for the detection of the 511 keV annihilation photons in PET, primarily because its density and atomic number give it a higher photoelectric efficiency than more conventional scintillators, such as NaI:Tl.
A large number of these dynamic tracer studies have been conducted throughout the world, resulting in important discoveries in heart disease, brain disorders and cancer.
PET is a medical imaging technique capable of measuring the concentration of labelled compounds in the human body as a function of time it is an efficient method for measuring regional biochemical and physiological functions. Of all known scintillators, cerium-doped Lu 2SiO 5 (LSO) has the best combination of density, atomic number, light output and speed for the detection of 511 keV annihilation photons in positron emission tomography (PET).
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