Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Values of the FMR/EPR parameters (Ai – amplitude, H0i – resonance field, ΔHi – linewidth) for four components (two in case of sample 3) of the observed spectra_ Each component has been attributed to a specific phase detected in XRD measurements_ In each case (except for sample 3 with Lorentzian lineshape) the Dysonian lineshape of a particular component was assumed_ Subscripts L and h stand for low and high field components of a specific phase, respectively_
| Sample | Parameter | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| A1[a.u] | H01[G] | ΔH1[G] | A2[a.u] | H02[G] | ΔH2[G] | A3[a.u] | H03[G] | ΔH3[G] | A4[a.u] | H04[G] | ΔH4[G] | |
| 1 | 8.8(1) | 285(5)(α-Fe(N))L | 3840(9) | 1.1(1) | 4225(5)(α-Fe(N))h | 2600(5) | 6.7(1) | 1890(5)(γ′-Fe4−xN)L | 4390(5) | 2.7(1) | 3250(5)γ′-Fe4−xN)h | 3270(5) |
| 2 | 6.9(1) | 260(5)(α-Fe(N))L | 3900(5) | 1.4(1) | 4560(5)(α-Fe(N))h | 3045(5) | 6.1(1) | 1920(5)(γ′-Fe4−xN)L | 4540(5) | 3.2(1) | 3410(5)(γ′-Fe4−xN)h | 3710(5) |
| 3 | 30(1) | 3340(5)(ε-Fex(N))h | 320(5) | 1.7(1) | 2910(5)(ε-Fex(N))L | 1960(5) | – | – | – | – | – | – |
| 4 | 7.1(1) | 155(5)(α-Fe(N))L | 4665(5) | 1.9(1) | 5260(5)(α-Fe(N))h | 3680(5) | 6.5(1) | 2210(5)(γ′-Fe4−xN)L | 5185(5) | 4.1(5) | 3890(5)(γ′-Fe4−xN)h | 4370(5) |
| 5 | 2.2(1) | 4770(5)(α-Fe(N))h | 4195(5) | 6.0(1) | 3370(5)(γ′-Fe4−xN)h | 5015(5) | 11.2(1) | 1385(5)(γ′-Fe4−xN)L | 6490(5) | 1.8(1) | ~ 0(20)(α-Fe(N))L | 2135(5) |
| 6 | 5.2(1) | 3355(5)(γ′-Fe4−xN)h | 6180(5) | 2.2(1) | 5300(5)(α-Fe(N))h | 5475(5) | 7.8(1) | 1090(5)(γ′-Fe4−xN)L | 5690(5) | 2.7(1) | 45(5)(α-Fe(N))L | 3000(5) |
Values of the effective uniaxial anisotropy field of different phases in investigated samples and relative integrated intensity ratio of α-Fe(N)/γ′-Fe4−xN phases calculated from FMR spectra_
| Sample | |||||||
|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | ||
| Effective uniaxial anisotropy field | Phase | ||||||
| α−Fe(N) | 2630(8) | 2860(8) | – | 3401(7) | 3182(8) | 3506(8) | |
| Ha [G] | γ′-Fe4−xN | 905(5) | 995(5) | – | 1123(5) | 1324(6) | 1512(6) |
| Relative integrated intensity ratio of α−Fe(N)/ γ′-Fe4−xN phases from FMR spectra | 0.86(2) | 0.70(2) | – | 0.71(2) | 0.08(1) | 0.20(2) | |