PULMONARY DEPOSITION AND RETENTION OF INHALED AEROSOLS

By SUSAN LEWIS

CONTENTS CHAPTER CRYSTAL STRUCTURE AT AMBIENT CONDITIONS CHAPTER TRANSPORT PROPERTIES UNDER AMBIENT CONDITIONS EXPERIMENTAL STUDIES OF THE ELECTRONIC STRUCTURE BAND STRUCTURE CALCULATIONS TRANSPORT PROPERTIES AND SEMICONDUCTOR-METAL PHASE TRANSITIONS UNDER HIGH PRESSURE PHASE TRANSITIONS IN CHAIN-TYPE CRYSTALS UNDER AMBIENT PRESSURE FERROELECTRIC PHASE TRANSITIONS AND INCOMMENSURATE STATES IN LAYERED CRYSTALS RELAXOR BEHAVIOR AND NANODOMAIN STRUCTURE OF DOPED AND IRRADIATED TLINS2 CRYSTALS LATTICE DYNAMICS IN 3B A AND C B A COMPOUNDS WITH TLSE- TYPE STRUCTURE VIBRATION SPECTRA OF MIXED CRYSTALS (SOLID SOLUTIONS) OF C B A COMPOUNDS CRYSTAL STRUCTURE AT AMBIENT CONDITIONS THE FAMILY OF THE BINARY AND TERNARY TLX AND TLMX2 (M = GA, IN; X = SE, S, TE) COMPOUNDS BELONGS TO A GROUP OF LOW-DIMENSIONAL SEMICONDUCTORS THAT POSSESS A CHAIN OR LAYERED STRUCTURE [1-14] ROOM TEMPERATURE X-RAY DIFFRACTION (XRD) AND NEUTRON DIFFRACTION MEASUREMENTS SHOWED THAT TLGASE2, TLGAS2 AND TLINS2 ARE LAYERED COMPOUNDS [1-6] FOR EXAMPLE, THE STRUCTURE OF TLGASE2 BELONGS TO THE MONOCLINIC SYMMETRY, THE SPACE GROUP IS Å) THE AVERAGE TL-TL SPACING IN THE CHAINS IS OF 3 81 Å THE SHORTEST TL-TL CONTACT BETWEEN THE TWO CHANNELS IS 4 38 Å [2] TLGAS2 AND TLINS2 ARE ISOSTRUCTURAL TO TLGASE2 [1, 3-6] THE STRUCTURAL PARAMETERS OF THE COMPOUNDS ARE GIVEN IN TABLES 1 1 AND 1 2 MONOCLINIC C C C H / 99 603O 100 6O 99 993O 2, 6, 100 21O 100 69O 11, TLS TETRAGONAL IN CONTRAST, TLSE, TLGATE2, TLINTE2 AND TLINSE2 SHOW A CHAIN STRUCTURE [7-10], OFTEN CALLED IN LITERATURE AS THE B37 TLSE TYPE THE CRYSTAL STRUCTURE OF TLSE [7, 10] BELONGS TO THE TETRAGONAL SYMMETRY, THE SPACE GROUP IS 2- TETRAHEDRA TL1+-SE DISTANCES ARE 3 43 Å, A LITTLE BIT SHORTER THAN THE SUM OF THE IONIC RADII OF TL1+ (1 59 Å FOR CN=8 [15]) AND SE2- (1 98 Å) THE TL1+ - TL1+ AND TL3+ - TL3+ DISTANCES IN THE CHAINS ARE 3 49 Å [7], WHILE THE DISTANCES BETWEEN THESE ATOMS IN THE (001) PLANE ARE 5 67 Å EACH TL1+ ION HAS FOUR TL3+ NEIGHBORS AT 4 01 Å IN THE A,B-PLANE, AND, IN REVERSE, EACH TL3+ ION HAS FOUR TL1+ NEIGHBORS AT THE SAME DISTANCE PROJECTIONS OF THE TLSE STRUCTURE ON THE A,B- AND A,C-PLANES ARE SHOWN IN FIGURE 1 2 PULMONARY DEPOSITION AND RETENTION OF INHALED AEROSOLS TL 1+ TL 3+ SE ARE THE Z/C NUMBERS (I E , POSITIONS OF THE ATOMS ABOVE THE A,B-PLANE, EXPRESSED AS A FRACTION OF THE UNIT CELL DIMENSION C) BOTTOM: PROJECTION OF THE TLSE CHAIN STRUCTURE ON THE A,C-PLANE PULMONARY DEPOSITION AND RETENTION OF INHALED AEROSOLS TABLE 1 3 STRUCTURES OF CHAIN-TYPE COMPOUNDS AT AMBIENT TEMPERATURE COMPOUND STRUCTURE SPACE GROUP A, Å C, Å Z REF TLSE TETRAGONAL MCM I D H / 6 791(2) TLS TETRAGONAL MCM I D H / TETRAGONAL MCM I D H / TLTE TETRAGONAL MCM I D H / INTE TETRAGONAL MCM I D H / 16, TL 4A GA 4B TE 8H 0 1700(3) 0 6700(3) IN 4B SE 8H 0 1714(5) 0 6714(5) TE 8H 0 1813(6) 0 6813(6) TLSE TL(1) 4A TL(2) 4B SE 8H 0 1784(3) 0 6784(3) TLS TL(1) 4A INTE IN(1) 4A IN(2) 4B FOR THALLIUM MONOSULFIDE, TLS, BOTH CHAIN (TETRAGONAL) AND LAYERED (MONOCLINIC) MODIFICATIONS HAVE BEEN OBTAINED [8, 11-13] THE FORMER ONE IS A MIXED VALENCE COMPOUND Å) THE S-TL(III)-S ANGLES ARE 117O AND 96O, DEVIATING FROM THE TETRAHEDRAL VALUE OF 109 5O; THE TETRAHEDRA ARE ELONGATED ALONG THE C-AXIS [13] THE TL3+ - S - TL3+ ANGLE IS ABOUT 84O THE TL1+-S DISTANCE IS 3 35 Å, A LITTLE BIT SHORTER THAN THE SUM OF THE EFFECTIVE IONIC RADII OF TL1+ (1 59 Å FOR CN= 8 [15]) AND S2- (1 84 Å [15]) THE TL1+ - TL1+ AND TL3+ - TL3+ DISTANCES IN THE CHAINS ARE 3 40 Å [11], WHILE THE DISTANCES BETWEEN THESE ATOMS IN THE (001) PLANE ARE 5 50 Å THE TL1+ - TL3+ DISTANCES IN THE A,B-PLANE ARE 3 89 Å THE LATTER, LAYERED MODIFICATION OF TLS [11-13] IS ISOSTRUCTURAL TO TLGASE2, WITH TL3+ IONS INSTEAD OF GA3+ IONS, AND BELONGS TO THE MONOCLINIC SYMMETRY (MORE EXPLICITLY, THE ROOM TEMPERATURE PHASE OF THE LAYERED TLS IS SHOWN TO BE ISOSTRUCTURAL TO THE LOW-TEMPERATURE PHASE OF TLGASE2, WHILE THE HIGH- TEMPERATURE PHASE OF THE LAYERED TLS IS ISOSTRUCTURAL TO THE ROOM-TEMPERATURE PHASE OF TLGASE2; WE WILL DISCUSS THIS POINT IN CHAPTER 7) FURTHERMORE, A LAYERED TETRAGONAL MODIFICATION OF TLS HAS ALSO BEEN REPORTED [12] THE STRUCTURAL PARAMETERS OF THE CHAIN AND LAYERED TLS MODIFICATIONS ARE GIVEN IN TABLES 1 1, 1 2, 1 3, AND 1 4 THE STRUCTURE OF TLTE (FIGURE 1 3) ALSO BELONGS TO THE TETRAGONAL SYMMETRY AND SPACE GROUP MCM I D H / [18, 19] HOWEVER, IT IS CONSIDERABLY DIFFERENT FROM THE STRUCTURE OF TLSE INSTEAD OF CRYSTALLIZING AS MIXED VALENCE COMPOUND TL1+TL3+(TE2-)2, IT FORMS A POLY- ANIONIC STRUCTURE FRAGMENTS, N N TE TL / 1) ( , REVEALING UNIVALENT TL+ CATIONS AND A POLYTELLURIC COUNTERPART WITH LINEAR EQUIDISTANT TE CHAINS IN THE [001] DIRECTION AT DISTANCES 3 0863 Å ONE HALF OF THESE CHAINS IS UNBRANCHED; THE OTHER ONE CONSISTS OF LINEAR [TE3]N UNITS STACKED CROSS- SHAPED ONE UPON THE OTHER FIGURE 1 3 CRYSTAL STRUCTURE OF THE ROOM TEMPERATURE PHASE OF TLTE ALONG THE [001] DIRECTION (FROM [19] WITH PERMISSION, © 2000 ELSEVIER ) THE CHEMICALLY DISTINCT TL1+ AND TL3+ IONS IN TLSE, AS WELL AS IN1+ AND IN3+ INTE, OCCUPY TWO DIFFERENT CRYSTALLOGRAPHIC POSITIONS, PREVENTING FREE TRANSFER OF ELECTRONS FROM THE UNIVALENT TO THE TRIVALENT ION THEREFORE ALL AFOREMENTIONED COMPOUNDS ARE SEMICONDUCTORS,