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How can we determine the cation distributions in CuFe2O4 or CoFe2O4 ?
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How can we determine the cation distributions in CuFe2O4 or CoFe2O4 ?
How did you calculate the intensity ratios without using the cation distributions? Do you mean you calculated the experimental values? Theoretically, There are many factors affecting the intensity of the diffracted X-rays spectrum, I, from powder samples such as the structure factor (F), multiplicity factor (MF), Lorentz factor (LF), polarization factor (PF), absorption factor (AF) and temperature factor (TF). These factors can be written as: I = (F)2 (MF) *(LF)*(PF)*(AF)*(TS) The multiplicity factor (MF) represents the number of the crystal planes, which have different orientations but with same spacing and structure factors. The values of the multiplicity factor for different crystalline structure planes can be found in many X-ray books.The polarization factor (PF) takes into account the X-rays diffracted part, which has connection with polarization property. The Lorentz factor (LF) for powder samples (which takes into account the sample size on the integrated intensity) depends on the diffraction angle. The polarization factor (PF) is usually combined with the Lorentz factor (LF) to give the combined Lorentz-Polarization factor, (LP)={[1+cos2(2θ)]/[sin2(θ).cos(θ)]}. Ignoring the temperature effects and after some approximation this equation will be reduced to: Ith = (Absolute F)2 * (MF) * (LP). Now you have to calculate F using the proposed cation distribution. At the end you are going to have the experimental and theoretical ratios of the intensity. If you find a differences between them you have to go back to the proposed cation distributions and changed it then redo the calculation. Repeat till you find the acceptable cation distributions. Good Luck
How did you calculate the intensity ratios without using the cation distributions? Do you mean you calculated the experimental values? Theoretically, There are many factors affecting the intensity of the diffracted X-rays spectrum, I, from powder samples such as the structure factor (F), multiplicity factor (MF), Lorentz factor (LF), polarization factor (PF), absorption factor (AF) and temperature factor (TF). These factors can be written as: I = (F)2 (MF) *(LF)*(PF)*(AF)*(TS) The multiplicity factor (MF) represents the number of the crystal planes, which have different orientations but with same spacing and structure factors. The values of the multiplicity factor for different crystalline structure planes can be found in many X-ray books.The polarization factor (PF) takes into account the X-rays diffracted part, which has connection with polarization property. The Lorentz factor (LF) for powder samples (which takes into account the sample size on the integrated intensity) depends on the diffraction angle. The polarization factor (PF) is usually combined with the Lorentz factor (LF) to give the combined Lorentz-Polarization factor, (LP)={[1+cos2(2θ)]/[sin2(θ).cos(θ)]}. Ignoring the temperature effects and after some approximation this equation will be reduced to: Ith = (Absolute F)2 * (MF) * (LP). Now you have to calculate F using the proposed cation distribution. At the end you are going to have the experimental and theoretical ratios of the intensity. If you find a differences between them you have to go back to the proposed cation distributions and changed it then redo the calculation. Repeat till you find the acceptable cation distributions. Good Luck
Dear all, All your advices are precious for my work. I'd like to thank Prof. Kadhim A. M. Khalaf, Prof. Philippe Tailhades and Kaustav Bhattacharjee. The cation distribution is clearly difficult to determine, and your responses helped me to figure out what I can do. I'll try to calculate the theorical intensities following the advice of Prof. Kadhim A. M. Khalaf as well as consider using other methods proposed by Kaustav Bhattacharjee and Prof. Philippe Tailhades. Thanks again and best regards
Dear all, All your advices are precious for my work. I'd like to thank Prof. Kadhim A. M. Khalaf, Prof. Philippe Tailhades and Kaustav Bhattacharjee. The cation distribution is clearly difficult to determine, and your responses helped me to figure out what I can do. I'll try to calculate the theorical intensities following the advice of Prof. Kadhim A. M. Khalaf as well as consider using other methods proposed by Kaustav Bhattacharjee and Prof. Philippe Tailhades. Thanks again and best regards
Normally, I use Fullprof software to analyze the diffraction patterns of our spinel sample. For example, I attatched herein the dat file of our sample CuFe2O4 annealed at 900oC and the pcr file used to carry out the Rietveld refinement. But I don't know how to obtain the cation distribution from these files. Can you show me how we can determine the cation distribution by Rietveld refinement method?
Normally, I use Fullprof software to analyze the diffraction patterns of our spinel sample. For example, I attatched herein the dat file of our sample CuFe2O4 annealed at 900oC and the pcr file used to carry out the Rietveld refinement. But I don't know how to obtain the cation distribution from these files. Can you show me how we can determine the cation distribution by Rietveld refinement method?
The method using the intensity ratios of the x-ray diffraction peaks requires very well crystallized materials. When the ferrites are poorly crystallized or in the form of fine powders, it is generally necessary to combine different methods to get the cations distribution. One simple way is to calculate for different assumptions, the lattice constants, for instance by the method of invariant cation oxygen distances (P. Poix Comptes Rendus Académie des Sciences C270 (1970) 1852) and the saturation magnetic moments using the colinear model of Neel. The comparison with the experimental data gives an idea of the real cation distribution. The difficulty is that CuFe2O4 is generally tetragonal. In this case, the calculation of the lattice constant cannot be donne properly by the method proposed. The paper in Journal of Magnetism and Magnetic Materials 334:66–73 · May 2013, will give you an illustration of the use of these methods combined with Mossbauer spectroscopy. I wish you a successful work!
The method using the intensity ratios of the x-ray diffraction peaks requires very well crystallized materials. When the ferrites are poorly crystallized or in the form of fine powders, it is generally necessary to combine different methods to get the cations distribution. One simple way is to calculate for different assumptions, the lattice constants, for instance by the method of invariant cation oxygen distances (P. Poix Comptes Rendus Académie des Sciences C270 (1970) 1852) and the saturation magnetic moments using the colinear model of Neel. The comparison with the experimental data gives an idea of the real cation distribution. The difficulty is that CuFe2O4 is generally tetragonal. In this case, the calculation of the lattice constant cannot be donne properly by the method proposed. The paper in Journal of Magnetism and Magnetic Materials 334:66–73 · May 2013, will give you an illustration of the use of these methods combined with Mossbauer spectroscopy. I wish you a successful work!
Dear Le, Thanks to RG that we can now discuss about our research problem in front of wide audience. Frankly speaking, I got stuck in same problem years ago, but then no RG was there. So, I had to sort this out myself alone. I read a lot about how to determine cations distribution in spinel ferrite and came into realization that, the accuracy of the distribution strongly depends on the accuracy of the instrumentation one is using. In my opinion, if you want to determine it precisely, do 1) slow scan PXRD and then perform Rietveld analysis by an expert (this analysis is also meticulous and sensitive to other parameters, so take advise of an expert). Or, 2) Perform Mossbauer or XANES kind of experiment which give you colsest accuracy of the distribution. Lastly, 3) I would suggest you to perform all these experiments and cross check the values that whether or not they differ from one experiment to other. Regards,
Dear Le, Thanks to RG that we can now discuss about our research problem in front of wide audience. Frankly speaking, I got stuck in same problem years ago, but then no RG was there. So, I had to sort this out myself alone. I read a lot about how to determine cations distribution in spinel ferrite and came into realization that, the accuracy of the distribution strongly depends on the accuracy of the instrumentation one is using. In my opinion, if you want to determine it precisely, do 1) slow scan PXRD and then perform Rietveld analysis by an expert (this analysis is also meticulous and sensitive to other parameters, so take advise of an expert). Or, 2) Perform Mossbauer or XANES kind of experiment which give you colsest accuracy of the distribution. Lastly, 3) I would suggest you to perform all these experiments and cross check the values that whether or not they differ from one experiment to other. Regards,
First off all, to the ans, there are no of experiments which can give you cation distribution, like....XRD, Mossbauer, XANES or even SQUID. But every expt has its own limitation. Thus exact quantification of the distribution is tough. Every case the analysis is mathematical. You can also use Rietveld refinement of the PXRD data to find out the distribution.
First off all, to the ans, there are no of experiments which can give you cation distribution, like....XRD, Mossbauer, XANES or even SQUID. But every expt has its own limitation. Thus exact quantification of the distribution is tough. Every case the analysis is mathematical. You can also use Rietveld refinement of the PXRD data to find out the distribution.
How did you calculate the intensity ratios without using the cation distributions?
Do you mean you calculated the experimental values?
Theoretically, There are many factors affecting the intensity of the diffracted X-rays spectrum, I, from powder samples such as the structure factor (F), multiplicity factor (MF), Lorentz factor (LF), polarization factor (PF), absorption factor (AF) and temperature factor (TF). These factors can be written as:
I = (F)2 (MF) *(LF)*(PF)*(AF)*(TS)
The multiplicity factor (MF) represents the number of the crystal planes, which have different orientations but with same spacing and structure factors. The values of the multiplicity factor for different crystalline structure planes can be found in many X-ray books.The polarization factor (PF) takes into account the X-rays diffracted part, which has connection with polarization property. The Lorentz factor (LF) for powder samples (which takes into account the sample size on the integrated intensity) depends on the diffraction angle. The polarization factor (PF) is usually combined with the Lorentz factor (LF) to give the combined Lorentz-Polarization factor, (LP)={[1+cos2(2θ)]/[sin2(θ).cos(θ)]}.
Ignoring the temperature effects and after some approximation this equation will be reduced to:
Ith = (Absolute F)2 * (MF) * (LP).
Now you have to calculate F using the proposed cation distribution. At the end you are going to have the experimental and theoretical ratios of the intensity. If you find a differences between them you have to go back to the proposed cation distributions and changed it then redo the calculation. Repeat till you find the acceptable cation distributions.
Good Luck
How did you calculate the intensity ratios without using the cation distributions?
Do you mean you calculated the experimental values?
Theoretically, There are many factors affecting the intensity of the diffracted X-rays spectrum, I, from powder samples such as the structure factor (F), multiplicity factor (MF), Lorentz factor (LF), polarization factor (PF), absorption factor (AF) and temperature factor (TF). These factors can be written as:
I = (F)2 (MF) *(LF)*(PF)*(AF)*(TS)
The multiplicity factor (MF) represents the number of the crystal planes, which have different orientations but with same spacing and structure factors. The values of the multiplicity factor for different crystalline structure planes can be found in many X-ray books.The polarization factor (PF) takes into account the X-rays diffracted part, which has connection with polarization property. The Lorentz factor (LF) for powder samples (which takes into account the sample size on the integrated intensity) depends on the diffraction angle. The polarization factor (PF) is usually combined with the Lorentz factor (LF) to give the combined Lorentz-Polarization factor, (LP)={[1+cos2(2θ)]/[sin2(θ).cos(θ)]}.
Ignoring the temperature effects and after some approximation this equation will be reduced to:
Ith = (Absolute F)2 * (MF) * (LP).
Now you have to calculate F using the proposed cation distribution. At the end you are going to have the experimental and theoretical ratios of the intensity. If you find a differences between them you have to go back to the proposed cation distributions and changed it then redo the calculation. Repeat till you find the acceptable cation distributions.
Good Luck
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ARTICLES YOU MAY BE INTERESTED IN,
If you are working in the feild of Spinel Ferrites
https://www.researchgate.net/publication/329554668_Multilevel_resistive_and_magnetization_switching_in_CuCoFe2O4Pt_device_Coexistence_of_ionic_and_metallic_conducting_filaments
https://www.researchgate.net/publication/323141836_Electroforming_Free_Controlled_Bipolar_Resistive_Switching_in_AlCoFe2O4FTO_device_with_Self-Compliance_Effect
ARTICLES YOU MAY BE INTERESTED IN,
If you are working in the feild of Spinel Ferrites
https://www.researchgate.net/publication/329554668_Multilevel_resistive_and_magnetization_switching_in_CuCoFe2O4Pt_device_Coexistence_of_ionic_and_metallic_conducting_filaments
https://www.researchgate.net/publication/323141836_Electroforming_Free_Controlled_Bipolar_Resistive_Switching_in_AlCoFe2O4FTO_device_with_Self-Compliance_Effect
More
VOTE
Dear all,
All your advices are precious for my work. I'd like to thank Prof. Kadhim A. M. Khalaf, Prof. Philippe Tailhades and Kaustav Bhattacharjee. The cation distribution is clearly difficult to determine, and your responses helped me to figure out what I can do. I'll try to calculate the theorical intensities following the advice of Prof. Kadhim A. M. Khalaf as well as consider using other methods proposed by Kaustav Bhattacharjee and Prof. Philippe Tailhades.
Thanks again and best regards
Dear all,
All your advices are precious for my work. I'd like to thank Prof. Kadhim A. M. Khalaf, Prof. Philippe Tailhades and Kaustav Bhattacharjee. The cation distribution is clearly difficult to determine, and your responses helped me to figure out what I can do. I'll try to calculate the theorical intensities following the advice of Prof. Kadhim A. M. Khalaf as well as consider using other methods proposed by Kaustav Bhattacharjee and Prof. Philippe Tailhades.
Thanks again and best regards
More
VOTE
Dear Behzad Abasht,
Normally, I use Fullprof software to analyze the diffraction patterns of our spinel sample. For example, I attatched herein the dat file of our sample CuFe2O4 annealed at 900oC and the pcr file used to carry out the Rietveld refinement. But I don't know how to obtain the cation distribution from these files. Can you show me how we can determine the cation distribution by Rietveld refinement method?
Yours sincerely,
Dear Behzad Abasht,
Normally, I use Fullprof software to analyze the diffraction patterns of our spinel sample. For example, I attatched herein the dat file of our sample CuFe2O4 annealed at 900oC and the pcr file used to carry out the Rietveld refinement. But I don't know how to obtain the cation distribution from these files. Can you show me how we can determine the cation distribution by Rietveld refinement method?
Yours sincerely,
More
VOTE
The method using the intensity ratios of the x-ray diffraction peaks requires very well crystallized materials.
When the ferrites are poorly crystallized or in the form of fine powders, it is generally necessary to combine different methods to get the cations distribution. One simple way is to calculate for different assumptions, the lattice constants, for instance by the method of invariant cation oxygen distances (P. Poix Comptes Rendus Académie des Sciences C270 (1970) 1852) and the saturation magnetic moments using the colinear model of Neel. The comparison with the experimental data gives an idea of the real cation distribution. The difficulty is that CuFe2O4 is generally tetragonal. In this case, the calculation of the lattice constant cannot be donne properly by the method proposed.
The paper in Journal of Magnetism and Magnetic Materials 334:66–73 · May 2013, will give you an illustration of the use of these methods combined with Mossbauer spectroscopy.
I wish you a successful work!
The method using the intensity ratios of the x-ray diffraction peaks requires very well crystallized materials.
When the ferrites are poorly crystallized or in the form of fine powders, it is generally necessary to combine different methods to get the cations distribution. One simple way is to calculate for different assumptions, the lattice constants, for instance by the method of invariant cation oxygen distances (P. Poix Comptes Rendus Académie des Sciences C270 (1970) 1852) and the saturation magnetic moments using the colinear model of Neel. The comparison with the experimental data gives an idea of the real cation distribution. The difficulty is that CuFe2O4 is generally tetragonal. In this case, the calculation of the lattice constant cannot be donne properly by the method proposed.
The paper in Journal of Magnetism and Magnetic Materials 334:66–73 · May 2013, will give you an illustration of the use of these methods combined with Mossbauer spectroscopy.
I wish you a successful work!
More
VOTE
Dear Le,
Thanks to RG that we can now discuss about our research problem in front of wide audience. Frankly speaking, I got stuck in same problem years ago, but then no RG was there. So, I had to sort this out myself alone. I read a lot about how to determine cations distribution in spinel ferrite and came into realization that, the accuracy of the distribution strongly depends on the accuracy of the instrumentation one is using.
In my opinion, if you want to determine it precisely, do 1) slow scan PXRD and then perform Rietveld analysis by an expert (this analysis is also meticulous and sensitive to other parameters, so take advise of an expert). Or, 2) Perform Mossbauer or XANES kind of experiment which give you colsest accuracy of the distribution. Lastly, 3) I would suggest you to perform all these experiments and cross check the values that whether or not they differ from one experiment to other.
Regards,
Dear Le,
Thanks to RG that we can now discuss about our research problem in front of wide audience. Frankly speaking, I got stuck in same problem years ago, but then no RG was there. So, I had to sort this out myself alone. I read a lot about how to determine cations distribution in spinel ferrite and came into realization that, the accuracy of the distribution strongly depends on the accuracy of the instrumentation one is using.
In my opinion, if you want to determine it precisely, do 1) slow scan PXRD and then perform Rietveld analysis by an expert (this analysis is also meticulous and sensitive to other parameters, so take advise of an expert). Or, 2) Perform Mossbauer or XANES kind of experiment which give you colsest accuracy of the distribution. Lastly, 3) I would suggest you to perform all these experiments and cross check the values that whether or not they differ from one experiment to other.
Regards,
More
VOTE
you can determine the cation distributions Rietveld refinement method.
you can determine the cation distributions Rietveld refinement method.
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VOTE
First off all, to the ans, there are no of experiments which can give you cation distribution, like....XRD, Mossbauer, XANES or even SQUID. But every expt has its own limitation. Thus exact quantification of the distribution is tough. Every case the analysis is mathematical.
You can also use Rietveld refinement of the PXRD data to find out the distribution.
First off all, to the ans, there are no of experiments which can give you cation distribution, like....XRD, Mossbauer, XANES or even SQUID. But every expt has its own limitation. Thus exact quantification of the distribution is tough. Every case the analysis is mathematical.
You can also use Rietveld refinement of the PXRD data to find out the distribution.
More
VOTE