Non-invasive precise thermometers working at the nanoscale with high spatial resolution, where the conventional methods are ineffective, have emerged over the last couple of years as a very active field of research. This has been strongly stimulated by the numerous challenging requests arising from nanotechnology and biomedicine. This critical review offers a general overview of recent examples of luminescent and non-luminescent thermometers working at nanometric scale. Luminescent thermometers encompass organic dyes, QDs and Ln 3+ ions as thermal probes, as well as more complex thermometric systems formed by polymer and organic-inorganic hybrid matrices encapsulating these emitting centres. Non-luminescent thermometers comprise of scanning thermal microscopy, nanolithography thermometry, carbon nanotube thermometry and biomaterials thermometry. Emphasis has been put on ratiometric examples reporting spatial resolution lower than 1 micron, as, for instance, intracellular thermometers based on organic dyes, thermoresponsive polymers, mesoporous silica NPs, QDs, and Ln 3+ -based up-converting NPs and b-diketonate complexes. Finally, we discuss the challenges and opportunities in the development for highly sensitive ratiometric thermometers operating at the physiological temperature range with submicron spatial resolution.

A unique Eu3+/Tb3+ luminescent self‐referencing nanothermometer allowing absolute measurements in the 10–350 K temperature range and sub‐micrometer spatial resolution is reported (see Figure). It has up to 4.9%·K−1 temperature sensitivity and high photostability for long‐term use. The combination of molecular thermometry, superparamagnetism and luminescence in a nanometric host matrix provides multifunctionality opening the way for new exciting applications.

group P2,,,; a =14.828(2). h = 11.513(1), c =16.637(2)A. 0 =112.735(4). V = 2619.5(5) A', 2 = 4 , pidlid =1.373 gem-,; p = 4.25 m m -' ; max. absorption correction factor l.60:20max =115,24';Cu,,radiation; T = 298K:O-28scan;reflectionscollectedjunique!used, 3767/3579 (R,,, = 0.0219)/3577; parameters refined, 352; Rl!xR2 [2794 reflections with I > 2a/], 0.0576/0.1579; GOF = 1.029; [ A / GI,,, = 0.003; [A&JAp]*," 0.373/ -0.308 eA-3, structure solution and refinement with the programs SHELXS-86 and SHELXL-93: H atoms of 1.10phenanthroline were located by difference maps and refined isotropically, the rest were introduced at calculated positions as riding on bonded atoms; all non-H atoms refined anisotropically (except atoms of the solvent methanol which refined isotropically with occupancy fixed at 10.5. Crystallographic data (excluding structure factors) for the structure reported in this paper have been deposited with the Cambridge Crystallographic Data Centre as supplementary publication no. CCDC-179-98. Copies of the data can be obtained free of charge on application to The Director, CCDC, 12 Union Road.

Conference Reports: Joel Miller of Du Pont describes activities at a recent NATO Advanced Research workshop on molecular magnetic materials held in Italy, and Siegmar Roth of the Max Planck Institute for Solid State Research in Stuttgart reports on a conference on synthetic metals held in southern Germany.