O₂-titrations accompanying ESR, adsorption isotherm and TPD studies of well-crystallised powdered rutile provide insights into the nature of the reduced surface following adsorption of propan-2-ol at 300 K. Estimates have been made of the mean dimensions of the octa-decahedral micro-crystallites, and of the manner in which UV-A radiation penetrates into a randomised particle-bed. The reduced surface contains a small fractional coverage (0.003monolayer) of paramagnetic Ti³⁺_A sites (1.1 × 10¹⁶ m⁻²) that appear to be associated mainly with the crystallite edges, and a large majority (>98%) of diamagnetically-coupled Ti³⁺_A-B spin-pairs arranged in the form of extended defects on the crystallite faces. UV-A is found to activate only a thin layer of particles at the bed exterior (0.83%) on which a large fraction (>30%) of the Ti⁴⁺_oct sites become reduced to paramagnetic Ti³⁺_A at 78 K, and mainly to spin-pairs at 300 K, with implications for their subsequent reactivity with oxidising gases.

结晶度高的金红石粉的ESR，吸附等温线和TPD研究所伴随的O ₂滴定提供了关于在300 K吸附丙-2-醇后还原表面性质的见解。十面体微晶体，以及UV-A辐射穿透随机颗粒床的方式。还原后的表面包含少量（0.003单层）的顺磁性Ti ³⁺ _A位点（1.1×10 ¹⁶  m ^-2），这些位点似乎主要与微晶边缘相关，而大部分（> 98％）的抗磁性耦合的Ti ³⁺ _A-B自旋对以微晶面扩展缺陷的形式排列。发现UV-A仅能活化床外表面的一薄层颗粒（0.83％），在78 K时，大部分的Ti ⁴⁺ _oct部位（> 30％）还原为顺磁性Ti ³⁺ _A，并且主要是在300 K时形成自旋对，这意味着它们随后会与氧化性气体发生反应。