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X-ray induced defect centres in commercial grade synthetic calcium fluorophosphate (FAP) doped with varying concentrations of Mn are studied through thermal glow curves and thermoluminescence spectra. Emission almost wholly occurs from Mn-centres during thermoluminescence (TL) but the emission wavelength varies; it occurs at 563 nm for concentrations of Mn up to 1% and at 574 nm for 10% Mn, and is attributed to Mn(II) and Mn(I) centres, respectively. Mn enhances the overall TL emission (for low concentrations) showing that the radiation induced defects are stabilised by Mn. Results reported here give a clue to understand the colour blending of FAP phosphors with different Mn concentrations. Rontgenstrahleninduzierte Defektzentren in synthetischen Kalziumfluorphosphat (FAP) kommerzieller Qualitat, das mit unterschiedlichen Konzentrationen von Mn dotiert wurde, werden mittels thermischer Glowkurven und Thermolumineszenzspektren untersucht. Die Emission ruhrt bei der Thermolumineszenz (TL) fast ausschlieslich von Mn-Zentren her, jedoch variiert die Emissionswellenlange sie tritt bei 563 nm fur Mn-Konzentrationen bis zu 1% und bei 574 nm fur 10% Mn auf und wird Mn(II)- bzw. Mn(I)-Zentren zugeordnet. Mn erhoht die Gesamt-TL-Emission (fur niedrige Konzentrationen), was darauf hinweist, das die strahleninduzierten Defekte durch Mn stabilisiert werden. Die mitgeteilten Ergebnisse geben einen Hinweis zum Verstandnis der Farbmischung von FAP-Phosphoren mit unterschiedlichen Mn-Konzentrationen.

The molecular cluster model, within the framework of the self-consistent field multiple scattering Xα method, is applied to calculate the electronic structure of a Mn substitutional impurity in GaAs. The charge states Mn3+, with spin configurations S = 0 and 2, and Mn2+, with S = 5 2 , were analysed. The theoretical results compare fairly well with the experimental data obtained from ESR and optical spectroscopic experiments.

We have studied by nuclear magnetic resonance (NMR) the system (SnTe)100-x Mnx. The knight shift of 119Sn and 125Te nuclei for undoped SnTe is temperature independent between 4.2 and 300 K. The variation of the Knight shift K(Sn) as a function of Mn concentration, at room temperature, has allowed us to obtain a value of the exchange integral between localized moments and charge carriers ; J = (0.22 ± 0.05) eV.

The hyperfine interactions of the first shell of Ga neighbors around ${\mathrm{Mn}}^{2+}$ on a Ga site in GaP are determined at 4.2 K by means of electron-nuclear double resonance (ENDOR) techniques. The spectrum could be described by use of the ENDOR spin Hamiltonian $\mathcal{H}=\stackrel{\ensuremath{\rightarrow}}{\mathrm{I}}\ifmmode\cdot\else\textperiodcentered\fi{}\stackrel{\ensuremath{\leftrightarrow}}{\mathrm{A}}\ifmmode\cdot\else\textperiodcentered\fi{}\stackrel{\ensuremath{\rightarrow}}{\mathrm{S}}+{Q}^{\ensuremath{'}}[{I}_{{x}_{q}}^{2}\ensuremath{-}\frac{1}{3}I(I+1)+\frac{1}{3}\ensuremath{\eta}({I}_{{y}_{q}}^{2}\ensuremath{-}{I}_{{z}_{q}}^{2})]\ensuremath{-}{g}_{N}{\ensuremath{\beta}}_{N}\stackrel{\ensuremath{\rightarrow}}{\mathrm{H}}\ifmmode\cdot\else\textperiodcentered\fi{}\stackrel{\ensuremath{\rightarrow}}{\mathrm{I}}$. The parameters of $^{71}\mathrm{Ga}$ are: $\frac{{A}_{{x}_{h}{x}_{h}}}{h}=+16.665\ifmmode\pm\else\textpm\fi{}0.004$ MHz, $\frac{{A}_{{y}_{h}{y}_{h}}}{h}=+14.186\ifmmode\pm\else\textpm\fi{}0.010$ MHz, $\frac{{A}_{{z}_{h}{z}_{h}}}{h}=+13.848\ifmmode\pm\else\textpm\fi{}0.008$ MHz, $\frac{{Q}^{\ensuremath{'}}}{h}=\ensuremath{-}1.493\ifmmode\pm\else\textpm\fi{}0.005$ MHz. $\ensuremath{\eta}=0.20\ifmmode\pm\else\textpm\fi{}0.02$, and $\frac{{g}_{N}{\ensuremath{\beta}}_{N}}{h}=+1.298\ifmmode\pm\else\textpm\fi{}0.003$ kHz/G. The ${x}_{h}$, ${y}_{h}$, and ${z}_{h}$ axes are the principal axes of $\stackrel{\ensuremath{\leftrightarrow}}{\mathrm{A}}$. The ${z}_{h}$ and ${z}_{q}$ axes coincide, and are along [$\overline{1}10$] for a Mn-Ga pair with axis along [110]. The angles between the pair axis and the ${x}_{h}$ and ${x}_{q}$ axes are 32.2\ifmmode\pm\else\textpm\fi{}0.2\ifmmode^\circ\else\textdegree\fi{} and 42.6\ifmmode\pm\else\textpm\fi{}0.3\ifmmode^\circ\else\textdegree\fi{}. respectively. The results for $^{69}\mathrm{Ga}$ are found to scale with those for $^{71}\mathrm{Ga}$ according to the ratios of the nuclear spins and the quadrupole moments. An attempt is made to interpret the data in terms of electron transfer and point-charge contributions.

The crystal-field splittings of the ground state of Mn in ${\mathrm{Cd}}_{1\ensuremath{-}x}{\mathrm{Hg}}_{x}\mathrm{Te}$ have been measured using electron paramagnetic resonance. The values are similar to those of Mn in II-VI compound semiconductors and are much smaller than the values assumed recently for Mn in semimagnetic semiconductor alloys.

Cathode ray coloration of Mn-doped CaF2 crystals is similar to that of undoped crystals; no new colour centres other than the α- and β-centres are formed. Results indicate that the β band formed by cathode ray irradiation around 560 nm is of an origin different from that of the 520 or 580 nm bands. The former band is suggested to be an aggregate centre band that involves F(α) centres also. The formation and behaviour of this band at different temperatures of irradiation is explained. Die Kathodenstrahlverfarbung von Mn-dotierten CaF2-Kristallen ist der von undotierten Kristallen ahnlich, es werden keine anderen Farbzentren als die α- und β-Zentren gebildet. Die Ergebnisse zeigen, das die β-Bande, die durch Kathodenbestrahlung bei 560 nm hervorgerufen wird, einen anderen Ursprung als die 520- oder 580 nm-Bande hat. Es wird angenommen, das sie eine Bande eines Assoziats ist, das auch F(α)-Zentren einschliest. Die Bildung und das Verhalten dieser Bande bei verschiedenen Bestrahlungstemperaturen wird erklart.

Growth of F absorption band with the time of X-irradiation at RT and the changes caused in the F absorption as a function of F light and thermal bleaching along with the simultaneous ESR studies in pure and Mn-doped LiF single crystals are reported.

Radiotracer techniques have been used to show that Zn diffusion into an originally uniformly Mn‐doped GaAs wafer produces marked changes in the Mn concentration profile, resulting in a large minimum behind and a small minimum ahead of the Zn diffusion front. A model which assumes that Mn is an amphoteric impurity in GaAs is proposed to explain these changes.

An EPR study of the Mn spectra in Li‐diffused Mn‐doped GaAs is presented. The EPR spectra show that the symmetry at the Mn site is orthorhombic. This thus indicates association between the Mn and Li impurities. A model is proposed which is consistent with the observed symmetry at the Mn site, the donor impurities, and with the infrared absorption of the localized vibrational modes of the Li impurities as observed by Lorimor and Spitzer.

An experimental study of the electrical resistivity in dilute Cu:Mn doped with Pt impurities is presented. The results indicate a suppression of the Kondo divergence in the conduction-electron scattering amplitude as a result of the spin-orbit interaction at the Pt impurities. The results are interpreted in terms of a reduction in the spin "memory" time.

The technique of Whitworth (1967) has been used to determine the charge per unit length on edge dislocations in NaCl crystals containing 116 p.p.m. of Mn++ ions. In crystals rapidly cooled from 400°c to keep many of the Mn++ ions and associated vacancies in solution, the dislocation charge increases with increasing amplitude of dislocation motion, and negative charges as large as one ionic charge per two cation sites on the dislocation core have been observed. When the dislocations are left at rest in the crystal for several hours their charges decrease and they become pinned. In contrast the dislocation charge does not increase appreciably when dislocations are moved in as-cleaved crystals in which the Mn++ ions and vacancies are mainly precipitated. These results are discussed in terms of the sweep-up of positive-ion vacancies, and the subsequent diffusion of these vacancies off the dislocation core and of Mn++ ions onto it.

This project has received funding from European Social Fund (project No 09.3.3-LMT-K-712-19-0069) under grant agreement with the Research Council of Lithuania (LMTLT). Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART². The World Federation of Scientists is highly acknowledged for the National Scholarship to AZ. © 2021. This work is licensed under a CC BY-NC-ND 4.0 license., In this work, a series of Mn2+-doped α-tricalcium phosphate (α-TCP) powders was synthesized by wet co-precipitation method followed by high-temperature annealing and thermal quenching. It was shown that Mn2+-doped α-TCP polymorph can be successfully synthesized with a doping level up to 1 mol%. All Mn-doped samples exhibited a broadband emission in the range from 525 to 825 nm with a maximum centered at around 630 nm. The highest emission intensity was observed for the sample with the highest content of Mn. The crystal structure and purity were evaluated by powder X-ray diffraction (XRD), Fourier-transform infrared (FTIR) and electron paramagnetic resonance (EPR) spectroscopies. Scanning electron microscopy (SEM) was used to investigate the morphological features of the synthesized products. Optical properties were investigated by means of photoluminescence measurements. Excitation spectra, emission spectra and decay curves of the samples were studied. Temperature-dependent photoluminescence measurements were performed as well.---- / / /---- This is the preprint version of the following article: Lauryna Sinusaite, Andris Antuzevics, Anatoli I. Popov, Uldis Rogulis, Martynas Misevicius, Arturas Katelnikovas, Aivaras Kareiva, Aleksej Zarkov, Synthesis and luminescent properties of Mn-doped alpha-tricalcium phosphate, Ceramics International 47 (4) (2021), https://doi.org/10.1016/j.ceramint.2020.10.114, which has been published in final form at https://www.sciencedirect.com/science/article/pii/S0272884220331540. This article may be used for non-commercial purposes in accordance with Elsevier Terms and Conditions for Sharing and Self-Archiving. This work is licensed under a CC BY-NC-ND 4.0 license., European Social Fund 09.3.3-LMT-K-712-19-0069; Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART².

The ion implantation process of Mn doped Si is examined with particular attention on the role of implantation temperature, implantation induced amorphisation and implantation damaged Si lattice recovery. It seems likely that Mn prefers to accumulate around the surface of Si nanometer scale crystals. Further work on reducing Mn segregation is proposed.

[Hypothesis]: Superparamagnetic MnxFe3-xO4 nanoparticles are promising materials for applications in biomedicine and other fields. Small variations in the Mn/Fe ratio have a strong impact on the properties of the nanoparticles. Those variations may be caused by the synthesis itself and by common post-synthesis manipulations like surface modification., [Experiments]: Mn-ferrite nanoparticles have been prepared changing systematically the Mn/Fe ratio of the metal precursors and repeating each reaction three times. Nanoparticles were subjected to surface modification with two different and typical molecules to stabilize them in aqueous media. The discrepancy in the Mn/Fe ratios of the precursors with the ones measured after the synthesis and the surface modification have been studied, as well as its impact on the saturation magnetization, blocking temperature, contrast enhancement for magnetic resonance imaging, magnetic heating, and on the cytotoxicity., [Findings]: Mn is incorporated in the nanoparticles in a relatively lower amount than Fe and, as this report shows for the first time, both Mn and Fe ions leach out from the nanoparticles during the surface modification step. The blocking temperature decreases exponentially as the Mn/Fe ratio increases. The transverse and longitudinal relaxation times and the magnetic heating ability change appreciably even with small variations in the composition., This work was supported by the Spanish Ministry of Economy and Competitiveness (project MAT2015-71806-R, SAF2017-87305-R, PGC2018-096016-B-I00), Comunidad de Madrid (projects P2018/NMT-4321, NANOMAGCOST-CM, and B2017/BMD-3867, RENIM-CM), and European Commission H2020 programme (project NOCANTHER, grant agreement no. 685795). IMDEA Nanociencia acknowledges support from the 'Severo Ochoa' Programme for Centres of Excellence in R&D (grant SEV-2016-0686). DG-S gratefully acknowledges Consejería de Educación, Juventud y Deporte de la Comunidad de Madrid y del Fondo Social Europeo (PEJD-2016/IND-2293 fellowship), PMR acknowledges support from the ‘Severo Ochoa’ Programme for Centres of Excellence in R&D (MINECO, Grant SEV-2016-0686), NLG thanks the Spanish Education Ministry for the funding (FPU18/02323) and Ayuntamiento de Madrid for the grant to live at Residencia de Estudiantes del CSIC. L.G. acknowledges financial support from the Ramón y Cajal program (RYC-2014-15512).

Precipitation of a phase identified as 6NaCl. MnCl2 has been studied by X-ray diffraction in slowly cooled single crystals of NaCl doped with MnCl2. The relevance of these observations to other studies of esr, clustering and mechanical properties in this system is discussed.

“Naively” calculated values of the dipolar EPR linewidth of Mn doped CaF 2 and PbF 2 are larger than those observed. This discrepancy is resolved when, in calculating the second and fourth moments, Mn ions with different values of m 55 are considered “unlike” and the contribution of exchange-coupled nearest neighbor ions is omitted.

The minority carrier (electron) diffusion length Ln was measured in Mn-doped p-type single crystals of InP. The surface photovoltage technique on electrolyte/InP diodes was employed. For samples with hole densities p ranging from 4.1 × 1014 cm−3 to 5.3 × 1016 cm−3 (296 K), Ln = 2.20 × 107/p0.43 μm. Ln does not appear to be affected by the high concentration of neutral Mn.

The presence of triple lithium ion centers (LiGa− 2Lii+)+ in lithium‐diffused GaP crystals previously doped with Mn is inferred from combined electron paramagnetic resonance (EPR) and electrical data.

The microscopic investigation of structural changes of bulk chalcogenide glasses and evaporated amorphous films by annealing and photoirradiation is carried out by the change of the ESR spectrum Mn doped as probe. The signal is found to change by the composition of the sample and by annealing. The change of the signal appears to be caused also by photoirradiation, but the reproducibility could not be established at the present stage. Although the present work is preliminary and a full understanding has not yet been achieved, the investigation of the change of the ESR signal is believed to be very useful in understanding the structural change from the microscopic point of view.

This paper was withdrawn after the proceedings had been assembled in its final form. In order to keep to a rapid publication schedule the succeeding pages have not been renumbered; pages 62 and 63 are therefore missing

In n-type GaP doping with Mn gives rise to a deep centre due to Mn+2. Its luminescence occurs in the near infrared.The behaviour of this centre is studied as a function of temperature and the thermal quenching of the luminescence interpreted as due to a non-radiative process to the ground state. The behaviour of another band that appears upon doping with Mn is also discussed.

Excitonic emissions observed in undoped and Mn-doped ZnS single crystals with cubic modification have been investigated by means of the temperature dependence of photo-luminescence intensity and the doublet structure. Reflectance spectrum at 4.2 K indicates that an exciton dip appears at 3.803 eV and the longitudinal-transverse splitting energy of free exciton is about 4 meV when 4πβ is 1.05×10-2 and ∈ is 8.1, respectively. Thermal dissociation energy of the free exciton is estimated to be about 40 meV. Assuming that the zero-phonon line associated with an Mn emission is ascribed to an isoelectronic-trap bound exciton, the doublet structure and thermal dissociation process are reasonably interpreted.

Electron paramagnetic resonance of Eu doped samarium chalcogenides and Mn doped samarium telluride show as much as 10% variations in g‐values from the usual value of S‐state ions near g ≈ 2. These shifts are caused by exchange interactions between the impurity and the Sm2+ ions.

Internal friction and Young's modulus measurements have been made on Fe and Mn doped β-NiAl alloys ranging from 4 to 20 at% Fe and from 5 to 15 at% Mn. It is found that the temperature dependent internal friction exhibits the same type of damping peak that is peculiar to a thermoelastic martensitic phase transformation. The internal friction peak is accompanied by characteristic anomalies on the temperature dependencies of Young's modulus. The effect of Ni content, rate of temperature change and duration of isothermal exposure on internal friction peak parameters and elastic anomalies has been investigated.

The optical and Raman spectroscopy of Mn2+ ions in dipolar form and forming Suzuki-phase precipitates has been studied in NaCl. An analysis of the position of the crystal field transitions reveals that the impurity-ligand distance is slightly smaller for the Suzuki phase but the covalency is the same for both phases. Finally it is demonstrated that the intense band at 231 nm is related to the existence of the Suzuki phase and not to the presence of small aggregates. This band has been reasonably assigned to the double excitation 6 A 1(S) + 6 A 1(S)↪4 T 1(G) + [6 A 1(G), 4 E(G)].

Following the theory, ferromagnetism is predicted in Mn- doped ZnO, Indeed, ferromagnetism above room temperature was recently reported in thin films as well as in bulk samples made of this material. Here, we have prepared Mn doped ZnO by electrodeposition. The samples have been characterized by X-ray diffraction and spectroscopic methods to ensure that the dopants are substitutional. Some samples exhibit weak ferromagnetic properties at room temperature, however to be useful for spintronics this material need additional carriers provided by others means.

We have measured the Mn 2p core absorption spectra of diluted magnetic semiconductors (DMS's) Hg1-x-yCdxMnyTe. We then performed the Mn 2p-3d resonance photoemission in order to reveal the Mn 3d electronic structures. The Mn 3d spectra have features similar to the Mn 3d spectra of other II-VI group DMS's with higher Mn concentration, which were reported by previous Mn 3p-3d resonance photoemission studies. Slight changes with Cd doping were observed in the Mn 3d photoemission and 2p absorption spectra.

The magnetizations residing on Mn impurities in K 2 NiF 4 and the first shell of Ni around them have been measured. From an analysis by Green's function techniques it appears that the impurity mode, having energy 0.15 z ∥ J ∥ S , is strongly localized and of s character.

The low field ac susceptibility, x'(T), of the mixed telluride Sn1-xPbxTe doped with Mn has been studied. Spin glass formation characterized by x'(T) going through a maximum at freezing temperature Tf has been observed. For a fixed Mn concentration Tf is observed to decrease as the Sn concentration decreases.

Coherence effects were studied in Al-I-(Mn)Al tunneling junctions. A decreasing zero bias resistivity anomaly was observed when increasing the barrier-impurity distance, with a correlation length of about 30° A. The anomaly due to the presence of small isolated metallic grains was eliminated.