Magnetic Solitons in the 1-D Antiferromagnetic Chains of Li₂Mn_0.98Fe_0.02F₅ and Na₂Mn_0.98Fe_0.02F₅

Abstract

Measurements of the

Magnetic Susceptibility Calculated from Correlation-Lengths Derived by Mössbauer Relaxation Spectra

“…The model given in (1) The characteristic Mössbauer parameters as quadrupole splitting and magnetic hyperfine field H are listed in Table 2 or are given in [6][7][8][9][10][11][12][19][20][21], The detailed theoretical analysis of domain wall dynamics and solitons in magnetic chains with a large local anisotropy D shows that, in a certain range above the critical temperature T N , the density of K domain walls and their motion determines the spin autocorrelation function (5(0)5(0), which is obtained by measuring the fluctuating hyperfine field H(t) ^ 5(f). The temperature dependence of the Mössbauer spectra for a representative powder sample of (NH 4 ) 2 Mn 0 98 Fe 0 02 F 5 (one of ten investigated fluoromanganates(HI) compounds) is shown in Figure 1.…”

“…4 [53] in the temperature range 1.7-330 K and external fields up to ±55 kG. The experimental procedure for determining the Neel temperatures has been described in detail in [12]. These transition temperatures 7" N are listed in Table 2.…”

“…Mössbauer effect in the iron-doped compounds of A 2 Mn ()98 Fe 002 F 5 (H 2 O) and AMno.9 8 Fe 0 .o2F 5 (H 2 0) [6][7][8][9][10][11][12], where we investigated the spin-dynamics and non-linear excitations (solitons) in these compounds. From the analysis of Mössbauer relaxation spectra based on the classical soliton model [13][14][15][16][17][18] we were able to determine the activation energy for such a soliton from the temperature dependence of the spin-fluctuation rate in the antiferromagnetic 1-d phase even of powder samples [8-10, 12, 19-21].…”

Struktur- und magnetochemische Untersuchungen an Ba5Mn3F19 und verwandten Verbindungen AII5MIII3F19

“…Dafu È r spricht auch die u È bereinstimmende Temperatur von 2,2 K, bei der fu È r Ba 5 Mn 3 F 19 und Pb 5 Mn 3 F 19 eine Divergenz der Magnetisierung zu beobachten ist, wenn nach vorangegangener Nullfeld-Einku È hlung im schwachen Feld (H = 50 G) erst erwa È rmt und anschlieûend wieder abgeku È hlt wird (1,8 ® 25 ® 1,8 K). In anderen Fa È llen hat sich gezeigt, daû diese Divergenztemperatur mit dem dreidimensionalen Ordnungspunkt T N zusammenfa È llt [35].…”

Ein Fluoridphosphat von Mangan(III) mit ungewöhnlicher Schichtstruktur: Na7[Mn5F13(PO4)3(H2O)3]

“…Anstieg der Magnetisierungswerte bei T = 3.3 K. Dies Verhalten in Verbindung mit einer unterhalb von T = 3.3 K zu beobachtenden Divergenz der Magnetisierungswerte ist charakteristisch fu È r einen magnetischen 3D-Phasenu È bergang (vgl. [20]). Nach Abb.…”