@article{fdi:010053164,
  title = {{L}ine-broadening effects in the powder infrared spectrum of apatite},
  author = {{B}alan, {E}tienne and {D}elattre, {S}. and {R}oche, {D}. and {S}egalen, {L}. and {M}orin, {G}. and {G}uillaumet, {M}. and {B}lanchard, {M}. and {L}azzeri, {M}. and {B}rouder, {C}. and {S}alje, {E}. {K}. {H}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he crystallinity of natural and synthetic apatite samples is often determined from the broadening of nu (4) {PO}4 infrared absorption bands. {H}owever, various physical mechanisms contribute to the observed linewidth. {I}n the present study, the factors determining the linewidth in the powder spectrum of synthetic fluorapatite and hydroxyapatite samples are investigated. {T}he temperature dependence of the infrared spectrum (10-270 {K}) is used to assess the respective contributions of homogeneous broadening, related to the decay of phonons through anharmonic coupling, and heterogeneous broadening related to elastic strain and macroscopic electrostatic effects. {T}his latter contribution is dominant in the investigated samples and depends on the shape of powder particles. {I}t is discussed under the light of the theoretical modeling of the low-frequency dielectric properties of apatite based on first-principles density functional theory calculations. {T}he linewidth of the weak nu (1) {PO}4 absorption band provides a reliable information on microscopic sources of broadening, i.e., apatite crystallinity. {I}n comparison, the other more intense {PO}4 bands are more sensitive to long-range electrostatic effects.},
  keywords = {{A}patite ; {I}nfrared spectroscopy ; {F}irst-principles calculations ; {A}nharmonicity},
  booktitle = {},
  journal = {{P}hysics and {C}hemistry of {M}inerals},
  volume = {38},
  numero = {2},
  pages = {111--122},
  ISSN = {0342-1791},
  year = {2011},
  DOI = {10.1007/s00269-010-0388-x},
  URL = {https://www.documentation.ird.fr/hor/fdi:010053164},
}