本文在探討兩種塊材化合物A0.1Mo2S2.9與SiMoS1+x (x≦1)，其各自擁有不同之晶格結構、電性與磁性。 A0.1Mo2S2.9樣品的XRD結果顯示，其中祇有Si0.1Mo2S2.9為單一的 Mo2S3結構，若摻雜物A為其它元素時，樣品都含有少量的Chevrel-phase雜相。 當摻雜的元素A為 碳、矽、鍺、硼與釕時，樣品具有抗磁性，其抗磁轉換溫度分別為4.08、4.23、3.82、4.62與4.35K， 而且在ρ-T圖上，可觀察到在相對應的溫度附近，其電阻率之斜率有明顯的變化，並且隨著磁場的增強而其電性轉折溫度也隨之降低。 在改變摻雜含量的實驗上，我們專注於擁有純相之SixMo2S3-x (x≦0.5)。其中Si0.33Mo2S2.67樣品的場冷(FC)及零場冷(ZFC)量測數據，顯示出在約63K時有類似鐵磁性的行為；而Si0.2Mo2S2.8 與 Si0.5Mo2S2.5 樣品的χ-T圖，則同時存在著二個不同溫度的抗磁轉換。

     另外，塊材化合物SiMoS1+x (0≦x≦1)則為MoS2與合金Mo3Si3之混合物，但是在x=0.4時樣品卻成為MoS2與MoSi2之混合物。 SiMoS1+x (0≦x≦1)樣品的常溫電阻率，會隨硫含量的增加而明顯變大，當x = 0, 0.2, 0.8, 1時，樣品分別在4.25、4.41、3.32與3.75K有明顯的電性斜率變化，其中 x = 0與1時，樣品分別在4.54與3.51K有抗磁轉變。

In this thesis, the Mo2S3 doped with Si, C, B, and Ru, is identified to bear the same crystalline structure P21/m as that of Mo2S3 through XRD analysis. Diamagnetic transitions with χm ~ 10-4 emu/g-Oe at temperature ranging from 2K to 6K were observed in the doped samples of SixMo2S3-x (x = 0.1, 0.2, 0.33, 0.5). And both of the x = 0.2 and 0.5 samples were found to have double diamagnetic transitions with higher Tc at the same temperature of 6.01K. While SixMo2S3-x of x = 0.33 displayed an extra ferromagnetic-like response at 63K. The corresponding transition in resistivity of SixMo2S3-x with x = 0.1 was noticed to show a mild drop with less than 10% of its original transition values as measured down to 2K. But a superconducting-like magnetic field dependence on the phase transition of resistivity was also noted. Its diamagnetic signals were greatly reduced when the applied magnetic fields were raised to 103 Oes. In the doped samples of A0.1Mo2S2.9 (A = C, B, and Ru) the phase transition in resistivity at 4.08K, 4.62K, and 4.35K, respectively, exhibited similar fashion as that in the case of Si0.1Mo2S2.9.
 
For the other bulk samples SiMoS1+x (0≦x≦1), the polycrystalline structure reveals a poorly-crystalline MoS2 phase with several unknown reflections. In SiMoS1.4 all of the unknown reflections could be identified belong to alloy MoSi2 structure, but it is the only sample which doesn’t show diamagnetic transitions. While in the XRD of the rest samples most of the unknown reflections may be assigned to alloy Mo3Si3 structure. The electrical transitions in resistivity of bulk sample SiMoS1+x with x = 0, 0.2, 0.8, and 1, are observed at 4.25K, 4.41K, 3.32K, and 3.75K, respectively. And the samples with x = 0 and 1, reveal diamagnetic transitions at 4.54K and 3.51K, respectively.

Contents

Chapter 1  Introduction.................................................................1
     1.1   A Brief Review of Superconducting Materials...............................1
1.2   Chevrel-Phases....................................................................................5
1.3   The Research Motivations................................................................12
	
Chapter 2  Literature Survey.....................................................18
2.1   Quasi One-Dimensional Structure of Mo2S3.............................18
     2.2   Overview of MoS2……......................................................................22
        2.3   The Alloys of MoSi2 and Mo5Si3.................................................28

Chapter 3  Experiments...............................................................31
3.1   Sample Preparation..........................................................................31
3.2   XRD Structural Analysis.................................................................32
     3.3   The Electrical Transport Measurements..........................................33
     3.4   The Magnetic Susceptibility Measurements....................................34
     
Chapter 4  Results and Discussions……………………………….35
     4.1   The Structural Analysis of A0.1Mo2S2.9 Bulk Samples……....................35
     4.2    The Electrical Properties of A0.1Mo2S2.9 Bulk Samples..................47
     4.3   The Electrical Properties of SixMo2S3-x with 0.1 ≦x ≦ 0.5
   Bulk Samples………………..……….…….…..…………..….…53
     4.4    The Magnetic Properties of SixMo2S3-x Bulk Samples...................57
     4.5   The Structural Analysis of SiMoS1+x Bulk Samples.......................63
     4.6   The Electrical Properties of SiMoS1+x Bulk Samples........................66
     4.7   The Magnetic Properties of SiMoS1+x Bulk Samples.......................73
     
Chapter 5 Conclusion.....................................................................76
References……………………………………………………………….79

List of Tables and Figures
Tables
Table 1.2-1   The superconducting compounds of sulfur and selenium…….….…...8
Table 1.3-1   The Tc(K) of Mx(Mo6Se8) compounds………….….….….….….…..16
Table 2.2-1   Crystal structure, ionic diameter, ionization potential, and 
             transition temperature of the alkali and alkaline-earth 
 intercalates of MoS2 listed in order of increasing ionic diameters…16
Table 4.1-1   The XRD refinement data of A0.1Mo2S2.9 at room temperature……40
Table 4.1-2   The XRD refinement parameters of Mo2S2.9 at room temperature…41
Table 4.1-3   The XRD refinement parameters of Si0.1Mo2S2.9 
at room temperature………………………………………….……42
Table 4.1-4   The XRD refinement parameters of C0.1Mo2S2.9 
at room temperature…………………………………………….……43
Table 4.5-1   The XRD data of Mo3Si3 alloy at room temperature…………..…65








Figures
Fig. 1.1-1     The history of superconducting materials……………….……………4
Fig. 1.2-1(a)   The elementary cell of rhombohedral structure of the Mo6S8…..……9
Fig. 1.2-1(b)   Building block arrangement structure of the MMo6S8………………9
Fig. 1.2-2(a)   Projection on the hexagonal plane. The three types of cavity
 are represented and large cations M are located in site 1…,………10
Fig. 1.2-2(b)   Distribution of small cations in the lattice…………………………..11
Fig. 1.2-3     Elements that have been reported as the ternary element in a 
Chevrel phase are shaded on the Periodic Table……………...….11
Fig. 1.3-1     The structural transition from rhombohedral R3 to triclinic P1  
   of Chevrel-phase superconductors at low temperature.………....….16
Fig. 1.3-2(a)  Inductive transitions of Mx(Mo6Se8) compounds...…………....….17
Fig. 1.3-2(b)  Inductive transitions of Mx(Mo6Se8) compounds...…………....….17
Fig. 1.3-3    The Tc of Mx(Mo6Se8) as a function of concentration……..….17
Fig. 2.1-1(a)  The model of Mo2S3 structure………………………………....….20
Fig. 2.1-1(b)  The model of Mo2S3 structure……….………………………....….20
Fig. 2.1-1(c)  The model of Mo2S3 structure…….…………….……………...….20
Fig. 2.1-1(d)  The model of Mo2S3 structure…….…….…..….……………....….20
Fig. 2.1-2    Relevant diffraction features at phase transitions…....……....….21
Fig. 2.1-3    Electrical resistivity of Mo2S3 along the crystalline b axis...….21
Fig. 2.2-1    The structure of MoS2……………………….…………….…....….25
Fig. 2.2-2(a)  The XRD patterns of MoSi2 from natural molybnite…………...….26
Fig. 2.2-2(b)  The XRD patterns of MoSi2 was prepared at 800°C…………...….26
Fig. 2.2-2(c)  The XRD patterns of MoSi2 was prepared at 600°C…………...….26
Fig. 2.2-2(d)  The XRD patterns of MoSi2 was prepared at 400°C…..…..…...….26
Fig. 2.2-3    Calculated X-ray diffraction patterns of small crystallites 
             of 2H-MoS2……..……….………………………………………..27
Fig. 2.3-1    The Cllb structure of MoSi2……..............………………………..29
Fig. 2.3-2    Two {110) planes of the Cllb structure………..…………………..30
Fig. 4.1-1    The XRD patterns of pure Mo2S3 structure.………….………....….38
Fig. 4.1-2    The XRD patterns of Mo2S3-x samples at room temperature…..........38
Fig. 4.1-3    The powder XRD patterns of A0.1Mo2S2.9 at room temperature…….….39
Fig. 4.1-4    The XRD patterns of Mo2S3 and A0.1Mo2S2.9 samples with 
 A= C, Si, Ge, at room temperature………….………......……....….40
Fig. 4.1-5    The XRD refinement patterns of Mo2S2.9 at room temperature......….41
Fig. 4.1-6    The XRD refinement patterns of Si0.1Mo2S2.9 at room temperature…..42
Fig. 4.1-7    The XRD refinement patterns of C0.1Mo2S2.9 at room temperature.…..43
Fig. 4.1-8(a)  The lattice parameters a and b of A0.1Mo2S2.9 at room temperature.....44
Fig. 4.1-8(b)  The lattice parameter c and volume of A0.1Mo2S2.9 at room
temperature………………………………………………………...…44
Fig. 4.1-9    The XRD patterns of SixMo2S3-x at room temperature………………………..45
Fig. 4.1-10   The XRD patterns of SiyMo2-yS3 at room temperature………………………..45
Fig. 4.1-11   The XRD patterns of PbxMo2S3-x at room temperature……………………….46
Fig. 4.1-12   The XRD patterns of CxMo2S3-x at room temperature………………………...46
Fig. 4.2-1    The resistivity as a function of temperature for AxMo2S3-x samples…..49
Fig. 4.2-2    The resistivity as a function of temperature for Si0.1Mo2S2.9 sample..50
Fig. 4.2-3    The resistivity as a function of temperature for Si0.1Mo2S2.9 
            sample with 0, 0.1, 0.3, and 0.6T magnetic fields……………...…..51
Fig. 4.2-4    The resistivity as a function of temperature for Si0.1Mo2S2.9 
            sample with 0, 0.05, 0.1, 0.15, 0.2, 0.25, and 0.5T magnetic fields..52
Fig. 4.3-1    The resistivity as a function of temperature for SixMo2S3-x 
            samples with x = 0.2, 0.33, and 0.5……………………..……....…..54
Fig. 4.3-2(a)  The resistivity as a function of temperature of Si0.2Mo2S2.8 
                   sample with enlarged scale….………..……………..……....…..55
Fig. 4.3-2(b)  The resistivity as a function of temperature of Si0.33Mo2S2.67 
            sample with enlarged scale…………………………...……....…..55
Fig. 4.3-2(c)  The resistivity as a function of temperature of Si0.5Mo2S2.5 
            sample with enlarged scale……………….…………...……....…..56
Fig. 4.4-1    The magnetic susceptibility of the bulk Si0.1Mo2S2.9 as a function 
            of temperature in the 15 and 1000Oe magnetic fields………..……..59
Fig. 4.4-2    The magnetic susceptibility of the bulk Si0.1Mo2S2.9 as a function 
            of temperature in the 50Oe magnetic field………………..……..60
Fig. 4.4-3    The magnetic susceptibility of the bulk Si0.1Mo2S2.9 as a function 
            of temperature in the 30Oe magnetic field………………..……..61
Fig. 4.4-4    The magnetic susceptibility of the bulk Si0.1Mo2S2.9 as a function 
            of temperature in the 30Oe magnetic field………………..……..62
Fig. 4.5-1    The XRD patterns of SiMoS1+x polycrystalline samples with
            x = 0 to 1…………………………………….……………………….64
Fig. 4.5-2   The XRD patterns of SiMoS1.4 polycrystalline samples 
            at room temperature……………………..………………………...65
Fig. 4.6-1    The temperature dependence on log electrical resistivity of 
       the bulk SiMoS1+x with x = 0, 0.2, 0.4, 0.8 and 1 samples………..67
Fig. 4.6-2    The temperature dependence on log electrical resistivity of 
       the bulk SiMoS sample……..………………………….………..68
Fig. 4.6-3    The temperature dependence on log electrical resistivity of 
       the bulk SiMoS1.2 sample……..………………………….………..69
Fig. 4.6-4    The temperature dependence on log electrical resistivity of 
            the bulk SiMoS1.4 sample……..………………………….………..69
Fig. 4.6-5    The temperature dependence on log electrical resistivity of 
            the bulk SiMoS1.8 sample……..………………………….………..70
Fig. 4.6-6    The temperature dependence on log electrical resistivity of 
       the bulk SiMoS2 sample……..………………………….………..71
Fig. 4.6-7    The temperature dependence on log electrical resistivity of 
       the bulk SiMoS3 sample……..………………………….………..72
Fig. 4.7-1    The magnetic susceptibility of the bulk SiMoS as a function 
            of temperature in the 50Oe magnetic field………………..……..74
Fig. 4.7-2    The magnetic susceptibility of the bulk SiMoS2 as a function 
       of temperature in the 50Oe magnetic field……….……..……..75
Fig. 5-1      The variations(Tc) dependence of ionic radius for A doped 
            into bulk A0.1Mo2S2.9 samples………………….…….……..……..78

References
[1]  H. Kamerlingh Onnes, Nature 86, 2169, pp. 419-420 (1911).
[2]  W. Meissner and R. Ochsenfeld, Naturwissenschaften 21, 787 (1933).
[3]  F. London and H. London, Proc. R. Soc. Lond. 149, 71-88 (1935).
[4]  V. L. Ginzburg and L. D. Landau, JETP 20, 1064 (1950).
[5]  Bardeen, Cooper and Schreiffer, Phys. Rev. Lett. 108, 1175 (1957).
[6]  F. London, Phys. Rev. Lett. 74, 562 (1948).
[7]  J. Bardeen, Phys. Rev. Lett. 97, 1724 (1955).
[8]  L. Cooper, Phys. Rev. Lett. 104, 1189 (1956).
[9]  Bardeen, Cooper and Schreiffer, Phys. Rev. Lett. 106, 162 (1957).
[10]  J. R. Gavaler, Appl. Phys. Lett. 23, 415 (1973).
[11]   J. G. Bednorz and K. A. Muller, Physik B Condensed Matter 64, 189 (1986).
[12]   J. M. Tarascon, L. H. Greene, W. R. Mckinnon, G. W. Hull and T. H. Geballe, Science 235, 1373 (1986).
[13]   M. K. Wu, J. R. Ashburn, C. J Torng, P. H. Hor, R. L. Meng, L. Gao, Z. J. Huang, Y. Q. Wang, and C. W. Chu, Phys. Rev. Lett. 58, 908 (1987).
[14]  H. Maeda, Y. Tanaka, M. Fukutomi and T. Asano, Jpn. J. Appl. Phys., 27, L209 (1988).
[15]   Z. Z. Sheng and A. M. Hermann, Nature, 332, 138 (1988).
[16]  L. Gao, Y. Y. Xue, F. Chen, Q. Xiong, R. L. Meng, D. Ramirez, C. W. Chu, J. H. Eggert, and H. K. Mao, Phys. Rev. B 50, 4260 (1994).
[17]  S. Nagata and T. Atake, Journal of Thermal Analysis and Calorimetry, 57, 809 (1999).
[18]   R. Chevrel, M. Sergent, and J. Prigent, J. Solid State Chem. 3, 515 (1971).
[19]  M. Sergent, R. Chevrel, J. Solid State Chem. 6, 433 (1973).
[20]  R. Chevrel, M. Sergent and J. Prigent, Mater. Res. Bull. 9, 1487 (1974).
[21]  O. Fischer, A. Treyvaud, R. Chevrel, and M. Sergent, Solid State Commun. 17, 721 (1975).
[22]  C. W. Chu, S. Z. Huang, C. H. Lin, R, L, Meng, and M. K. Wu, Phys. Rev. Lett. 46, 276 (1981).
[23]  J. W. Lynn, G. Shirane, W. Thomlinson, and R. N. Shelton, Phys. Rev. Lett. 46, 368 (1981).
[24]  P. H. Hor, M. K. Wu, T. H. Lin, X. Y. Shao, X. C. Jin, and C. W. Chu, Solid State Commun. 44, 1605 (1982).
[25]  J. M. Tarascon, J. V. Waszczak, G. W. Hull, F. J. DiSalvo, and L. Blitzer, Solid State Commun. 47, 973 (1983).
[26]  D. W. Capone II, R. P. Guertin, S. Foner,  D. G. Hinks, and Huang-Chen Li, Phys. Rev. Lett., 51, 601 (1983).
[27]  J. M. Tarascon, F. J. DiSalvo, D. W. Murphy, G. Hull, and J. V. Waszczak, Phys. Rev. B 29, 172 (1984). 
[28]  O. Fischer, Appl. Phys., 16, 1 (1978).
[29]  C Roche, P Pecheur, G Toussaint, A Jenny, H Scherrer and S Scherrer, J. Phys. Condens. Matter, 10, L333 (1998).
[30]  O. Fischer, and M. B. Maple, general review Topics in Current Physics, (Springer-Verlag, New York) 32 and 34, (1983).
[31]  T. Saito, Advances in Inorganic Chemistry, (1996).
[32]  C. P. Poole Jr., H. A. Farach, and R. J. Creswick, Superconductivity, (Academic Press) p.78 (1995).
[33]  I. Giaever and K. Megerle, Phys. Rev. Lett., 122, 1101 (1961).
[34]  Y. Kamihara, T. Watanabe, M. Hirano, and H. Hosono, Journal of the American Chemical Society, 130, 3296 (2008).
[35]  H. Takahashi et al., Nature, 453, 376 (2008).
[36]  D. C. Johnson, J. M. Tarascon, and M. J. Sienko, Inorg. Chem., 24, 2598 (1985).
[37]  H. W. Meul., Helv. Phys. Acta, 59, 417 (1986).
[38]   J. D. Jorgensen, D. G. Hinks, and G. P. Felcher, Phys. Rev. B, 35, 5365 (1987).
[39]  F. C. Hsu, J. Y. Luo, K. W. Yeh, T. K. Chen, T. W. Huang, P. M. Wu, Y. C. Lee, Y. L. Huang, Y. Y. Chu, D. C. Yan, and M. K. Wu, Proc. Natl. Acad. Sci. U.S.A., 105, 14262 (2008)
[40]  J. Beille, H. Schmitt, O. Pena, J. Padiou, and M. Sergent, J. Phys. Condens. Matter, 3, 2471 (1991).
[41]  C. W. Chu, S. Z. Huang, C. H. Lin, R. L. Meng, and M. K. Wu, Phys. Rev. Lett., 46, 276 (1981).
[42]  F. Le Berre, O. Pena, C. Hamard, A. Corrignan, R. Horyn, and A. Wojakowski, J. Alloys and Compounds, 262-263, 331 (1997).
[43]  C. W. Chu et al., Nature, 365, 323 (1993).
[44]  B. C. Sales, A. S. Sefat, M. A. McGuire, R. Y. Jin, and D. Mandrus, Phys. Rev. B, 79, 94521 (2009).
[45]  J. Guo, S. Jin, G. Wang, S. Wang, K. Zhu, T. Zhou, M. He, and X. Chen, Phys. Rev. B, 82, 180520 (2010).
[46]  A. A. Opalovskii and V. E. Fedorov, Izv. Akad. Nauk SSSR Neorg. Mater., 2, 443 (1966).
[47]  R. DeJonge, T. Popma, G. Wiegers, and F. Jellinek, J. Solid State Chem., 2, 188 (1970).
[48]  M. H. Rashid, D. J. Sellmyer, V. Katkanant, and R. D. Kirby, Solid State Commun., 43, 675 (1982).
[49]  R. Deblieck, G. A. Wiegers, K. D. Bonsema, D. van Dyck, G. van Tendeloo, J. van Landuyt and S. Amelinckx, Phys. Status Solidi A, 77, 249 (1983).
[50]  A. I. Romanenko, F. S. Rakhmenkulov, I. N. Kuropyatnik, and V. E. Fedorov, and A. V. Mishchenko, Phys. Stat. Sol. (a), 84, 165 (1984).
[51]  A. I. Romanenko, F. S. Rakhmenkulov, V. N. lkorskii, and P. S. Nikitin, Pis’ma Zh. Eksp. Teor. Fiz., 42, 377 (1985).
[52]  Alova and G. Mozurkewich, J. Phys. (Paris) Colloq., 46, C10-685 (1985).
[53]  R. L. Fagerquist and Roger D. Kirby, Phys. Rev. B, 38, 3973 (1988).
[54]  R. L. Fagerquist, Roger D. Kirby, and E. A. Pearlstein, Phys. Rev. B, 39, 5139 (1989).
[55]  Adilgiry A. Kusor and Roger D. Kirby, Phys. Rev. B, 50, 373 (1994).
[56]  J. A. Wilson and A. D. Yoffe, Advan. Phys., 18, 193 (1969).
[57]  R. B. Somoano, and A. Rembaum, Phys. Rev. Lett., 27, 402 (1971).
[58]  John A. Woollam and Robert B. Somoano, Phys. Rev. B, 13, 3843 (1976).
[59]  F. Jellinek, G. Brauer and H. Mũller, Nature, 185, 376 (1960).
[60]  R. E. Bell, and R. E. Herfert, J. Amer. Chem. Soc., 79, 3351 (1957).
[61]  F. Z. Chien, S. C. Moss, K. S. Liang and R. R. Chianelli, J. Phys. Colloques, 42, C4-273 (1981).
[62]  E. Diemann, and A. Muller, Coord. Chem., 432, 127 (1977).
[63]  R. R. Chianelli, and M. B. Dines, Inorg. Chem., 17, 2758 (1978).
[64]  R. R. Chianelli, E. B. Prestridge, R. A. Pecoraro, and J. P. De Neufville, Science, 203, 1105 (1979).
[65]  A. J. Jacobson, R. R. Chianelli, S. M. Rich, and M. S. Whittingham, Mat. Res. Bull., 14, 1473 (1979).
[66]  A. J. Jacobson, R. R. Chianelli, and M. S. Whittingham, J. Electrochem. Soc. Soc., 126, 2277 (1979).
[67]  W. Rudorff, Chimia, 19, 489 (1965).
[68]  B. L. Evans and P. A. Young, Proc. Roy. Soc. Ser. A, 284, 402 (1965)
[69]  J. A. Wilson and A. D. Yoffe, Advan. Phys., 18, 193 (1960).
[70]  B. T. Matthias, and J. K. Hulm, Phys. Rev. Lett., 87, 799 (1952).
[71]  R. B. Somoano, V. Hadek, and A. Rembaum, J. Chem. Phys., 58, 697 (1973).
[72]  A. M. Hermann, R. B. Somoano, V. Hadek, and A. Rembaum, Solid State Commun., 13, 1065 (1973).
[73]  R. B. Somoano, V. Hadek, A. Rembaum, S. Samson, and J. A. Woollam, J. Chem. Phys., 62, 1068 (1975).
[74]  R. Deblieck, G. A. Wigers, K. D. Bronsema, Physica Status Solidi (a), 77, 249 (1983).
[75]  O. Hoenigschmid, Monatsh. Chem., 28, 1017 (1907).
[76]  A. K. Vasudevan and J. J. Petrovic, Mater. Sci. Eng. A, 155, 1 (1992).
[77]  J. J. Petrovic and A. K. Vasudevan, Mater. Res. Soc. Symp. Proc., 273, 229 (1992).
[78]  J. J. Petrovic, Mater. Res. Soc. Bull., 18, 35 (1993).
[79]  O. K. Andersen, O. Jepsen, VI. N. Antonov, V. N. Antonov, B. Yu. Yavorsky, A. Ya. Perlov, and A. P. Shpak, Physica B, 204, 65 (1995).
[80]  K. Ito, M. Moriwaki, T. Nakamoto, H. Inui, and M. Yamaguchi, Mater. Sci. Eng. A, 233, 33 (1997).