Structure, Magnetism, and Tunable Negative Thermal Expansion in

Aug 17, 2017 - ACS eBooks; C&EN Global Enterprise. A; Accounts of Chemical ..... Crystal and magnetic structure of (Hf1–xNbx)Fe2 alloys. Temperature...
0 downloads 0 Views 1MB Size
Download PDF
Communication pubs.acs.org/cm

Structure, Magnetism, and Tunable Negative Thermal Expansion in (Hf,Nb)Fe2 Alloys Yuzhu Song,† Jun Chen,*,† Xinzhi Liu,‡ Chinwei Wang,§ Qilong Gao,† Qiang Li,† Lei Hu,† Ji Zhang,∥ Shantao Zhang,∥ and Xianran Xing† †

Department of Physical Chemistry, University of Science and Technology Beijing, Beijing 100083, China Helmholtz-Zentrum-Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, D-14109 Berlin, Germany § Neutron Group, National Synchrotron Radiation Research Center, Hsinchu 30077, Taiwan ∥ National Laboratory of Solid State Microstructures and Department of Materials Science and Engineering, College of Engineering and Applied Science & Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China ‡

S Supporting Information *

A

measurements. A complete research on the complex magnetic behavior and crystal structure reveals the NTE mechanism in the (Hf1−xNbx)Fe2 alloys. The present method of the coexistence of NTE and PTE phases could be used to design alloys with controllable thermal expansion property. HfFe2 as the end member of (Hf1−xNbx)Fe2 alloys forms in the mixed phases of cubic MgCu2-type and hexagonal MgZn2type structures at the room temperature.33,34 However, after the Nb substitution for Hf, MgZn2-type hexagonal structure is stabilized for all investigated compositions of (Hf1−xNbx)Fe2 (0.05 ≤ x ≤ 0.2) (space group, P63/mmc, Figure S1). The synchrotron XRD data of x = 0.1 can be well refined according to the above structural model (Figure S2). Taking (Hf0.9Nb0.1)Fe2 for instance, Fe1, Fe2, and Hf/Nb atoms occupy Wyckoff sites 2a (0, 0, 0), 6h (x, 2x, 1/4), and 4f (1/3, 2/3, z), respectively (Figure 1). Its crystal structure consists of

minute shape change, caused by the normal thermal expansion on heating, may degrade the excellent performance of materials. Consequently, it is necessary to explore negative thermal expansion (NTE) compounds to compensate positive thermal expansion (PTE) of most materials.1,2 Up to now, great progress has been achieved in the development of new NTE compounds, such as cyanides,3,4 oxides,5−8 nitrides,9,10 fluorides,11,12 alloys.13−15 It has be well-known that alloys have relatively better performance, not only in mechanical property but also in thermal and electron conductivity properties. Therefore, it is meaningful to extend the scope of NTE alloy families. So far, there have some alloys have been discovered to exhibit abnormal thermal expansion, such as Invar alloys of Fe0.65Ni0.35,16,17 Th2Zn17-type compounds of R2Fe17 (R = rare earth elements, Y, Pr, Dy, Ho, Er, Tm) and R2Fe17Cx compounds with R = Y, Tb, Tm,18−20 NaZn13-type intermetallic of La(Fe,Si)13,21 and MnCoGe-based compounds.22 The control of thermal expansion, which means not only coefficient of thermal expansion (CTE) but also temperature range can be tailored, is important for the practical applications of NTE materials. There are various effective methods to tune thermal expansion, such as chemical modification, size effect, and application of external pressure. Generally, thermal expansion is controlled through changing the interplay between lattice, electron, and phonon, such as modulating the amount of charge transfer in BiNiO323,24 and LaCu3Fe4O12,25 changing framework flexibility in zinc dicyanometallates,26 decreasing the particle size of CuO, 27 adjusting spontaneous volume ferroelectrostriction (SVFS) in the PbTiO3-based ferroelectrics,28 tuning the flexibility of atomic linkage in MZrF6 (M = Ca, Mn, Fe, Co, Ni, and Zn),29 controlling the magnetic transition in antiperovskite Mn3AN (A = Zn and Ga) nitrides.9,30−32 Here, we report an intriguing NTE in the magnetic alloys of (Hf1−xNbx)Fe2 (0 < x ≤ 0.15), which covers room temperature. Especially, its thermal expansion can be controlled by the coexistence of NTE magnetic and PTE paramagnetic phases. Crystal structure, magnetism, and NTE mechanism have been revealed by the joint studies of temperature dependence of conventional and synchrotron X-ray diffraction (XRD), neutron powder diffraction (NPD), and macroscopic magnetic © 2017 American Chemical Society

Figure 1. Crystal and magnetic structure of (Hf1−xNbx)Fe2 alloys.

alternating layers of iron hexahedrons, stacked parallel to the c-axis. The magnetic structure of (Hf1−xNbx)Fe2 has been determined by analyzing the NPD data. As an example, the observed and calculated NPD patterns of x = 0.1 at 10 K are shown in Figure S3a. The propagation vector of (Hf0.9Nb0.1)Fe2 magnetic structure is k = (0, 0, 0), because there are no additional peaks and only an additional contribution to the nuclear peaks are observed. The magnetic unit cell is identical Received: June 21, 2017 Revised: August 17, 2017 Published: August 17, 2017 7078

DOI: 10.1021/acs.chemmater.7b02563 Chem. Mater. 2017, 29, 7078−7082

Communication

Chemistry of Materials to the nuclear cell.35 The refinement of NPD pattern confirms that (Hf0.9Nb0.1)Fe2 is ferromagnetic at 10 K. As depicted in Figure 1, magnetic moments of Fe at the 2a and 6h sites are in the ab plane and parallel to the a(b)-axis. Temperature evolution of XRD has been carried out to investigate thermal expansion property of (Hf1−xNbx)Fe2 (0.05 ≤ x ≤ 0.15). Figure 2 displays temperature dependence of unit

Figure 3. Temperature dependences of zero-field-cooling (ZFC) and field-cooling (FC) magnetization at a magnetic field of 0.005 T for the (Hf1−xNbx)Fe2 alloys of (a) x = 0.05, (b) x = 0.1, and (c) x = 0.15, and (d) TC as a function of x.

Figure 2. Temperature dependence of unit cell volume of (Hf1−xNbx)Fe2 alloys (x = 0.05, 0.075, 0.1, 0.125, and 0.15). Those values at the NTE range for the x = 0.125 and 0.15 are the average ones of the two phases.

Here, the unit cell shrinks due to the factor of smaller Nb, resulting in the decrease of Fe−Fe bond length and the weakened positive exchange interaction. Theoretically, when the exchange interaction is weakened, the compound absorbs less thermal energy to break magnetic ordering. Therefore, the ferromagnetic transition temperature tends to decrease with increasing Nb content. The magnetic transition temperatures for all compounds are consistent with the temperatures of NTE disappearing, which indicates that the NTE phenomenon has a particularly close connection with the magnetic behavior. It also needs to note that there is an unusual inflection below the ferromagnetic transition temperature. The reason is due to different behavior of magnetic moments of iron, which will be discussed later. A set of selected magnetic isothermals were measured with increasing and decreasing field (Figure S7). All compositions of x = 0.075, 0.1, 0.125, and 0.15 are macroscopically ferromagnetic at low temperature. As shown in Figure S8, the magnetization almost reaches saturated at high fields of 7 T for x = 0.075, 0.1, and 0.15, but not for x = 0.2. It indicates that nonferromagnetic state is present in the x = 0.2 sample at low temperature. It should be mentioned that the magnetic behavior of the present (Hf1−xNbx)Fe2 (0.05 ≤ x ≤ 0.2) alloys is similar to that of the (Hf1−xTax)Fe2 specimens.37,38 To illuminate the NTE mechanism, we have carried out temperature dependence of synchrotron XRD and NPD for (Hf0.9Nb0.1)Fe2. Both lattice parameters (a, c) and interatomic distances between different iron sites are extracted from the results of structure refinement. As shown in Figure 4a, the NTE of (Hf0.9Nb0.1)Fe2 is dominated by the NTE along the a(b)axis, whereas the c-axis almost linearly expands with increasing temperature. Similarly, the distance of Fe(6h)−Fe(6h) is shorten in the NTE range, whereas that of Fe(2a)−Fe(6h) expands. Intuitively, the NTE of (Hf0.9Nb0.1)Fe2 is accompanied by the in-plane shrinkage of iron hexahedrons (Figure 1). The detailed relationship between NTE and magnetic behavior is revealed by the analysis of NPD data of (Hf0.9Nb0.1)Fe2. Figure 4b shows the temperature dependence of the (002) diffraction intensity of NPD. The intensity decreases gradually as the ferromagnetic contribution becomes

cell volume ranging from 173 to 473 K. Please note that the values of unit cell volume of x = 0.125 and 0.15 are the average ones, because there exists the coexistence of two phases in the NTE range, which will be discussed later. Interestingly, one can see that unit cell volume contracts continuously with increasing temperature in a certain temperature range, i.e., NTE occurs. With increasing the substitution content of Nb, NTE temperature range moves gradually from high to low temperatures. Simultaneously, NTE is weakened, and its temperature region becomes broadened with the examples of x = 0.05 (αv = −23.13 × 10−6 K−1, 323−398 K, ΔT = 75 K), x = 0.1 (αv = −21.6 × 10−6 K−1, 273−373 K, ΔT = 100 K), x = 0.125 (αv = −17.92 × 10−6 K−1, 248−373 K, ΔT = 125 K), and x = 0.15 (αv = −8.28 × 10−6 K−1, 173−323 K, ΔT = 150 K). To check the reliability of NTE property, a good agreement can be found for the temperature dependence of unit cell volume for x = 0.1 that has been derived from both NPD and synchrotron XRD data (Figure S4). The thermal expansion property of (Hf0.85Nb0.15)Fe2 was determined at even lower temperature by NPD. The temperature dependence of unit cell volume of x = 0.15 is shown in Figure S5. PTE occurs below 130 K, whereas NTE in the temperature range of 130−300 K with αv = −9.26 × 10−6 K−1. It needs mention that the present alloys of (Hf1−xNbx)Fe2 show a strong NTE property that covers the room temperature range. For example, the CTE of (Hf0.9Nb0.1)Fe2 is similar to that of ZrW2O8 (αv = −27.3 × 10−6 K−1, 0−300 K)1 and PbTiO3 (αv = −19.9 × 10−6 K−1, 298−763 K).36 To investigate the detailed magnetic behavior of (Hf1−xNbx)Fe2 (0.05 ≤ x ≤ 0.2), temperature dependence of zero-fieldcooling (ZFC) and field-cooling (FC) magnetization was measured at a magnetic field of 0.005 T (Figure 3). From the derivative curves of FC-ZFC, we can obtain the ferromagnetic Curie temperatures (TC), which are 390, 373, 324, and 217 K for x = 0.075, 0.1, 0.15, and 0.2, respectively. It monotonously decreases with increasing content of Nb (Figure 3d). The lattice parameters (a and c) and unit cell volume (V) exhibit a similar linear decrease as a function of Nb content (Figure S6). 7079

DOI: 10.1021/acs.chemmater.7b02563 Chem. Mater. 2017, 29, 7078−7082

Communication

Chemistry of Materials

a smaller volume. Therefore, NTE occurs with increasing temperature (ΔV < 0).16 Because of the increasingly disordered paramagnetic state, the magnetic entropy increases upon heating (ΔS > 0, ΔV and ΔS are the molar volume and molar entropy differences of two phases). Therefore, for these NTE compounds, when volume is reduced at a constant temperature (ΔV < 0), the magnetic ordering will be damaged, i.e., ΔS > 0.42 The fundamental criterion that the NTE materials possess NTE characteristics, i.e., ΔV < 0 and ΔS > 0, has been studied in details in the Reference 42. For the compositions of x = 0.125 and 0.15 with a higher content of Nb, an XRD profile splitting happens in the NTE temperature range, which is apparent for the {hk0} index, but not for the {00l} one (Figure S9). However, for the compositions with a lower Nb content, no profile splitting occurs. For example, Figure 5a,b manifest the contour plots of Figure 4. Temperature dependence of crystal and magnetic structure of (Hf0.9Nb0.1)Fe2. (a) Lattice parameters and Fe−Fe interatomic distances, (b) (002) peak intensity of NPD, (c) magnetic moments of different Fe sites, and (d) dM/dT, and dV/dT.

weak, and then keeps on a nearly constant nuclear intensity at ∼370 K, which is consistent with the TC (373 K) extracted from the FC-ZFC data (Figure 3). Temperature dependence of magnetic moments of different Fe sites is shown in Figure 4c. Interestingly, there is an apparent difference in not only magnitude but also disappearing temperature for both magnetic moments of Fe(2a) and Fe(6h) iron sites. Because of such desynchrony behavior, the unusual inflection can be found below the TC at FC-ZFC curves (Figure 3). It has been known that in iron-rich compounds magnetic moment is sensitive to local environment,39 and the different iron sites have distinct Fe−Fe magnetic exchange couplings that cause different magnetic moments. To find the correlation between magnetic moment (M) and NTE, Figure 4d shows the rates of magnetization (dM/dT) and unit cell volume (dV/dT) with respect to temperature. The value of M, calculated by 3/2MFe(6h)+1/2MFe(2a), is the total magnetic moment for one chemical formula. Three stages can be observed for dM/dT. When the magnetic moment decreases slowly at the lower temperature, the unit cell volume increases, i.e. PTE happens. However, when the magnetic moment drops quickly in the intermediate temperature range, the unit cell volume begins to contract, i.e., NTE occurs. Both dM/dT and dV/dT reaches their minimum value at TM (the temperature at which the Fe(2a) magnetic moment disappears). The decrease of total magnetic moment and unit cell volume become slow again between TM and TC. At temperature above TC, the lattice of paramagnetic phase expands normally, because there is only contribution from the inherent anharmonicity of phonon vibrations. The direct relationship between magnetic moment and unit cell volume explains the NTE mechanism of the present alloys of (Hf,Nb)Fe2. The decrease in Fe magnetic moments of the ab plane results in the shrinkage of the unit cell along the ab plane. The present NTE mechanism supports the magnetovolume effect (MVE) that corresponds to the NTE happening in magnetic materials, such as Invar alloy,16 (Hf 0.86 Ta 0.14 )Fe 2 , 37 antiperovskite manganese nitrides Mn3Cu0.5Ge0.5N,40 La(Fe,Si,Co)13,21 and Er2Fe17.41 The NTE mechanism can be also understood according to the role of magnetic entropy in MVE. For the compound of (Hf,Nb)Fe2, an ordered ferromagnetic phase at large volume gradually transforms to a disordered paramagnetic one that has

Figure 5. Contour plots of the (013) and (112) XRD profile intensity for (a) x = 0.1, and (b) x = 0.15 as a function of temperature. (c) The mass fraction, and (d) unit cell volume of FM and PM phases of x = 0.15 as a function of temperature.

the (013) and (112) XRD peak intensity for x = 0.1 and x = 0.15, respectively. One can directly see that in the x = 0.15 sample the (112) peak splits into two peaks in the NTE temperature range of 173−300 K, whereas the (013) peak has no visible splitting. It indicates the phenomenon of phase separation occurs in the x = 0.15. However, there is no profile splitting at the whole temperature rage, because (Hf0.9Nb0.1)Fe2 is single FM phase. The Rietveld analysis of XRD patterns indicates that the profile splitting of (Hf0.85Nb0.15)Fe2 originates from the coexistence of two hexagonal phases, which share the same space group P63/mmc but slightly different lattice parameters (Figure S9). To further study the magnetic properties of such coexisted phases, the temperature dependence of NPD was measured for (Hf0.85Nb0.15)Fe2 at 10−345 K. It is important to note that there are no additional peaks in the diffraction pattern for (Hf0.85Nb0.15)Fe2 beyond those expected for a single FM phase (Figure S3b). The existence of antiferromagnetic phase can be therefore excluded. The character of nonsaturated magnetism indicates that there is a paramagnetic phase coexisting with the FM phase (Figure S8). Additionally, unit cell volume of one phase follows a good correlation for 7080

DOI: 10.1021/acs.chemmater.7b02563 Chem. Mater. 2017, 29, 7078−7082

Communication

Chemistry of Materials temperatures above and below TC, which also indicates the nature of PTE phase is paramagnetic (Figure 5d). To study the possibility of compositional inhomogeneity for the phase coexistence, we have carried out some analyses of energy dispersive spectroscopy (EDS) and full width at halfmaximum (FWHM) of XRD peaks in the Supporting Information. According to the present experiments, no apparent compositional inhomogeneity was observed in the samples. However, we cannot exclude the possibility of compositional inhomogeneity to the existence of phase coexistence, because it could have the effect on the level of nanoscale. In general, the phase separation behavior can be caused by the thermodynamic competition between distinct physical states with similar free energies over a large temperature interval.43,44 We need to mention that such a phenomenon of phase coexistence can be sometimes observed in other systems,45−47 such as two AFM phases coexistence in the antiperovskite nitride of Mn3ZnN,44 two monoclinic phases below ∼300 K in the double perovskite Ca2FeReO6,43 and the coexistence of AFM and FM phases in Hf1−xTaxFe2 (x = 0.225).33 The exact mechanism of phase separation in the present (Hf,Nb)Fe2 alloys needs to be studied in future. Temperature dependence of the relative mass fraction and unit cell volume between FM and PM phases were determined by the Rietveld analysis for x = 0.15 (Figure 5c,d). With increasing temperature, the FM phase fraction decreases gradually in the NTE temperature range (173−323 K), and then disappears around 323 K. Simultaneously, the PM phase shows an opposite trend (Figure 5c). As shown in Figure 5d, the FM phase is NTE (αv = −18.96 × 10−6 K−1) but the PM one is PTE (αv = 24.13 × 10−6 K−1), resulting in an average one to be low thermal expansion (αv = −8.28 × 10−6 K−1, 173−323 K). The same behavior of the coexistence of NTE ferromagnetic and PTE paramagnetic phases occurs in other compositions with lower Nb content, such as (Hf0.875Nb0.125)Fe2 (Figure S12). Interestingly, the coexistence of NTE ferromagnetic and PTE paramagnetic phases can be utilized to reduce thermal expansion of (Hf1−xNbx)Fe2 alloys, such as large NTE in x = 0.05 (αv = −23.13 × 10−6 K−1, 323−398 K, ΔT = 75 K) to low thermal expansion in x = 0.15 (αv = −8.28 × 10−6 K−1, 173−323 K, ΔT = 150 K). Therefore, the NTE of (Hf1−xNbx)Fe2 originates from ferromagnetic phase, and thermal expansion can be adjusted by the coexistence of NTE magnetic phase and PTE paramagnetic one. In summary, crystal and magnetic structure of NTE magnetic alloys of (Hf1−xNbx)Fe2 are studied by the synchrotron XRD and NPD in details. Direct NPD experimental evidence shows that the NTE of FM phase originates from magnetovolume effect, i.e., the quick decrease of Fe moments in the ab plane causes the shrinkage of unit cell. The magnetic moment is different at two iron sites in the ferromagnetic phase, which explains the abnormal phenomenon in the FC-ZFC curves. Furthermore, the coexistence of NTE ferromagnetic and PTE paramagnetic phases tunes negative thermal expansion by changing the amount of PM phase in the (Hf1−xNbx)Fe2 compounds.

■

■

Materials synthesis, experimental details, data analysis procedures (PDF)

AUTHOR INFORMATION

Corresponding Author

*J. Chen. E-mail: [email protected]. ORCID

Jun Chen: 0000-0002-7330-8976 Xianran Xing: 0000-0003-0704-8886 Notes

The authors declare no competing financial interest.

■

ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China (Grant Nos. 91422301, 21231001, and 21590793), the Program for Changjiang Scholars and the Innovative Research Team in University (IRT1207), the Changjiang Young Scholars Award, the National Program for Support of Top-notch Young Professionals, and the Fundamental Research Funds for the Central Universities, China (Grant No. FRF-TP-14-012C1). The synchrotron radiation experiments were performed at the BL44B2 of Spring-8 with the approval of the Japan Synchrotron Radiation Research Institute (JASRI) (Proposal No. 2016A1060). Variable temperature neutron powder diffraction (NPD) data was collected at the high-intensity diffractometer Wombat of the Australian Nuclear Science and Technology Organisation (ANSTO).

■

REFERENCES

(1) Mary, T. A.; Evans, J. S. O.; Vogt, T.; Sleight, A. W. Negative Thermal Expansion from 0.3 to 1050 K in ZrW2O8. Science 1996, 272, 90−92. (2) Takenaka, K. Negative Thermal Expansion Materials: Technological Key for Control of Thermal Expansion. Sci. Technol. Adv. Mater. 2012, 13, 013001. (3) Goodwin, A. L.; Calleja, M.; Conterio, M. J.; Dove, M. T.; Evans, J. S.; Keen, D. A.; Tucker, M. G.; Peters, L. Colossal Positive and Negative Thermal Expansion in the Framework Material Ag3[Co(CN)6]. Science 2008, 319, 794−797. (4) Goodwin, A. L.; Kepert, C. J. Negative Thermal Expansion and Low-Frequency Modes in Cyanide-Bridged Framework Materials. Phys. Rev. B: Condens. Matter Mater. Phys. 2005, 71, 140301. (5) Evans, J. S. O.; Mary, T. A.; Vogt, T.; Subramanian, M. A.; Sleight, A. W. Negative Thermal Expansion in ZrW2O8 and HfW2O8. Chem. Mater. 1996, 8, 2809−2823. (6) Tucker, M. G.; Goodwin, A. L.; Dove, M. T.; Keen, D. A.; Wells, S. A.; Evans, J. S. Negative Thermal Expansion in ZrW2O8: Mechanisms, Rigid Unit Modes, and Neutron Total Scattering. Phys. Rev. Lett. 2005, 95, 255501. (7) Evans, J. S. O.; Hanson, P. A.; Ibberson, R. M.; Duan, N.; Kameswari, U.; Sleight, A. W. Low-Temperature Oxygen Migration and Negative Thermal Expansion in ZrW2‑xMoxO8. J. Am. Chem. Soc. 2000, 122, 8694−8699. (8) Allen, S.; Evans, J. S. O. Negative Thermal Expansion and Oxygen Disorder in Cubic ZrMo2O8. Phys. Rev. B: Condens. Matter Mater. Phys. 2003, 68, 134101. (9) Takenaka, K.; Takagi, H. Giant Negative Thermal Expansion in Ge-doped Anti-perovskite Manganese Nitrides. Appl. Phys. Lett. 2005, 87, 261902. (10) Iikubo, S.; Kodama, K.; Takenaka, K.; Takagi, H.; Takigawa, M.; Shamoto, S. Local Lattice Distortion in the Giant Negative Thermal Expansion Material Mn3Cu1−xGexN. Phys. Rev. Lett. 2008, 101, 205901. (11) Greve, B. K.; Martin, K. L.; Lee, P. L.; Chupas, P. J.; Chapman, K. W.; Wilkinson, A. P. Pronounced Negative Thermal Expansion

ASSOCIATED CONTENT

S Supporting Information *

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.chemmater.7b02563. 7081

DOI: 10.1021/acs.chemmater.7b02563 Chem. Mater. 2017, 29, 7078−7082

Communication

Chemistry of Materials from A Simple Structure: Cubic ScF3. J. Am. Chem. Soc. 2010, 132, 15496−15498. (12) Attfield, J. P. Condensed-Matter Physics: A Fresh Twist on Shrinking Materials. Nature 2011, 480, 465−466. (13) Mohn, P. Materials Science: A Century of Zero Expansion. Nature 1999, 400, 18−19. (14) Khmelevskyi, S.; Turek, I.; Mohn, P. Large Negative Magnetic Contribution to the Thermal Expansion in Iron-Platinum Alloys: Quantitative Theory of the Invar Effect. Phys. Rev. Lett. 2003, 91, 037201. (15) Mohn, P.; Schwarz, K.; Wagner, D. Magnetoelastic Anomalies in Fe-Ni Invar Alloys. Phys. Rev. B: Condens. Matter Mater. Phys. 1991, 43, 3318−3324. (16) van Schilfgaarde, M.; Abrikosov, I. A.; Johansson, B. Origin of the Invar Effect in Iron−Nickel Alloys. Nature 1999, 400, 46−49. (17) Guillaume, C. É. Recherches sur les aciers au nickel. Dilatations Aux Températures élevées; Résistance électrique. CR. Acad. Sci. 1897, 125, 18. (18) Hao, Y.; Gao, Y.; Wang, B.; Qu, J.; Li, Y.; Hu, J.; Deng, J. Negative Thermal Expansion and Magnetic Properties of Y2Al3Fe14−xMnx compounds. Appl. Phys. Lett. 2001, 78, 3277−3279. (19) Andreev, A. V.; De Boer, F. R.; Jacobs, T. H.; Buschow, K. H. J. Thermal Expansion Anomalies and Spontaneous Magnetostriction in R2Fe17Cx Intermetallic Compounds. Phys. B 1991, 175, 361−369. (20) Dan, S.; Mukherjee, S.; Mazumdar, C.; Ranganathan, R. Zero Thermal Expansion with High Curie Temperature in Ho 2 Fe 16 Cr Alloy. RSC Adv. 2016, 6, 94809−94814. (21) Huang, R.; Liu, Y.; Fan, W.; Tan, J.; Xiao, F.; Qian, L.; Li, L. Giant Negative Thermal Expansion in NaZn13-Type La(Fe, Si, Co)13 compounds. J. Am. Chem. Soc. 2013, 135, 11469−11472. (22) Zhao, Y. Y.; Hu, F. X.; Bao, L. F.; Wang, J.; Wu, H.; Huang, Q. Z.; Wu, R.-R.; Liu, Y.; Shen, F.-R.; Kuang, H.; et al. Giant Negative Thermal Expansion in Bonded MnCoGe-Based Compounds with Ni2In-Type Hexagonal Structure. J. Am. Chem. Soc. 2015, 137, 1746− 1749. (23) Oka, K.; Nabetani, K.; Sakaguchi, C.; Seki, H.; Czapski, M.; Shimakawa, Y.; Azuma, M. Tuning Negative Thermal Expansion in Bi1−xLnxNiO3 (Ln= La, Nd, Eu, Dy). Appl. Phys. Lett. 2013, 103, 061909. (24) Azuma, M.; Chen, W. T.; Seki, H.; Czapski, M.; Olga, S.; Oka, K.; Mizumaki, M.; Watanuki, T.; Ishimatsu, N.; Kawamura, N.; et al. Colossal Negative Thermal Expansion in BiNiO3 Induced by Intermetallic Charge Transfer. Nat. Commun. 2011, 2, 347. (25) Long, Y. W.; Hayashi, N.; Saito, T.; Azuma, M.; Muranaka, S.; Shimakawa, Y. Temperature-Induced A−B Intersite Charge Transfer in An A-Site-Ordered LaCu3Fe4O12 Perovskite. Nature 2009, 458, 60− 63. (26) Goodwin, A. L.; Kennedy, B. J.; Kepert, C. J. Thermal Expansion Matching via Framework Flexibility in Zinc Dicyanometallates. J. Am. Chem. Soc. 2009, 131, 6334−6335. (27) Zheng, X. G.; Kubozono, H.; Yamada, H.; Kato, K.; Ishiwata, Y.; Xu, C. N. Giant Negative Thermal Expansion in Magnetic Nanocrystals. Nat. Nanotechnol. 2008, 3, 724−726. (28) Chen, J.; Wang, F.; Huang, Q.; Hu, L.; Song, X.; Deng, J.; Yu, R.; Xing, X. Effectively Control Negative Thermal Expansion of SinglePhase Ferroelectrics of PbTiO3-(Bi, La)FeO3 over A Giant Range. Sci. Rep. 2013, 3, 2458. (29) Hu, L.; Chen, J.; Xu, J.; Wang, N.; Han, F.; Ren, Y.; Pan, Z.; Rong, Y.; Huang, R.; Deng, J.; et al. Atomic Linkage Flexibility Tuned Isotropic Negative, Zero, and Positive Thermal Expansion in MZrF6 (M= Ca, Mn, Fe, Co, Ni, and Zn). J. Am. Chem. Soc. 2016, 138, 14530−14533. (30) Iikubo, S.; Kodama, K.; Takenaka, K.; Takagi, H.; Shamoto, S. Magnetovolume Effect in Mn3Cu1−xGexN Related to the Magnetic Structure: Neutron Powder Diffraction Measurements. Phys. Rev. B: Condens. Matter Mater. Phys. 2008, 77, 020409. (31) Deng, S.; Sun, Y.; Wu, H.; Huang, Q.; Yan, J.; Shi, K.; Malik, M. I.; Lu, H.; Wang, L.; Huang, R.; et al. Invar-Like Behavior of

Antiperovskite Mn3+xNi1−xN Compounds. Chem. Mater. 2015, 27, 2495−2501. (32) Lin, J. C.; Tong, P.; Tong, W.; Lin, S.; Wang, B. S.; Song, W. H.; Zou, Y. M.; Sun, Y. P. Tunable Negative Thermal Expansion Related with the Gradual Evolution of Antiferromagnetic Ordering in Antiperovskite Manganese Nitrides Ag1−xNMn3+x (0≤ x≤ 0.6). Appl. Phys. Lett. 2015, 106, 082405. (33) Bag, P.; Singh, S.; Babu, P. D.; Siruguri, V.; Rawat, R. Study of Antiferro−Ferromagnetic Phase Coexistence in Ta Doped HfFe2. Phys. B 2014, 448, 50−52. (34) Livi, F. P.; Rogers, J. D.; Viccaro, P. J. Experimental Studies of Hyperfine Interactions and Magnetization in HfFe2. Phys. Status Solidi (a). 1976, 37, 133−138. (35) Rodríguez-Carvajal, J.; Bourée, F. Symmetry and Magnetic Structures. EDP. EPJ Web Conf. 2012, 22, 00010. (36) Chen, J.; Xing, X.; Yu, R.; Liu, G. Thermal Expansion Properties of Lanthanum-Substituted Lead Titanate Ceramics. J. Am. Ceram. Soc. 2005, 88, 1356−1358. (37) Li, B.; Luo, X. H.; Wang, H.; Ren, W. J.; Yano, S.; Wang, C. W.; Gardner, J. S.; Liss, K.-D.; Miao, P.; Lee, S.-H.; et al. Colossal Negative Thermal Expansion Induced by Magnetic Phase Competition on Frustrated Lattices in Laves Phase Compound (Hf, Ta)Fe2. Phys. Rev. B: Condens. Matter Mater. Phys. 2016, 93, 224405. (38) Rechenberg, H. R.; Morellon, L.; Algarabel, P. A.; Ibarra, M. R. Magnetic Moment at Highly Frustrated Sites of Antiferromagnetic Laves Phase Structures. Phys. Rev. B: Condens. Matter Mater. Phys. 2005, 71, 104412. (39) Isnard, O.; Fruchart, D. Magnetism in Fe-Based Intermetallics: Relationships between Local Environments and Local Magnetic Moments. J. Alloys Compd. 1994, 205, 1−15. (40) Song, X.; Sun, Z.; Huang, Q.; Rettenmayr, M.; Liu, X.; Seyring, M.; Li, G.; Rao, G.; Yin, F. Adjustable Zero Thermal Expansion in Antiperovskite Manganese Nitride. Adv. Mater. 2011, 23, 4690−4694. (41) Á lvarez-Alonso, P.; Gorria, P.; Blanco, J. A.; Sánchez-Marcos, J.; Cuello, G. J.; Puente-Orench, I.; Rodríguez-Velamazán, J. A.; Garbarino, G.; de Pedro, I.; Fernández, J. R.; et al. Magnetovolume and Magnetocaloric Effects in Er2Fe17. Phys. Rev. B: Condens. Matter Mater. Phys. 2012, 86, 184411. (42) Liu, Z. K.; Wang, Y.; Shang, S. L. Origin of Negative Thermal Expansion Phenomenon in Solids. Scr. Mater. 2011, 65, 664−667. (43) Granado, E.; Huang, Q.; Lynn, J. W.; Gopalakrishnan, J.; Greene, R. L.; Ramesha, K. Spin-orbital Ordering and Mesoscopic Phase Separation in the Double Perovskite Ca2FeReO6. Phys. Rev. B: Condens. Matter Mater. Phys. 2002, 66, 064409. (44) Sun, Y.; Wang, C.; Huang, Q.; Guo, Y.; Chu, L.; Arai, M.; Yamaura, K. Neutron Diffraction Study of Unusual Phase Separation in the Antiperovskite Nitride Mn3ZnN. Inorg. Chem. 2012, 51, 7232− 7236. (45) Božin, E. S.; Kwei, G. H.; Takagi, H.; Billinge, S. J. L. Neutron Diffraction Evidence of Microscopic Charge Inhomogeneities in the CuO2 Plane of Superconducting La2−xSrxCuO4 (0≤ x ≤ 0.30). Phys. Rev. Lett. 2000, 84, 5856. (46) Moritomo, Y.; Kuwahara, H.; Tomioka, Y.; Tokura, Y. Pressure Effects on Charge-Ordering Transitions in Perovskite Manganites. Phys. Rev. B: Condens. Matter Mater. Phys. 1997, 55, 7549. (47) Huang, Q.; Lynn, J. W.; Erwin, R. W.; Santoro, A.; Dender, D. C.; Smolyaninova, V. N.; Ghosh, K.; Greene, R. L. Temperature and Field Dependence of the Phase Separation, Structure, and Magnetic Ordering in La1−xCaxMnO3 (x = 0.47, 0.50, and 0.53). Phys. Rev. B: Condens. Matter Mater. Phys. 2000, 61, 8895.

7082

DOI: 10.1021/acs.chemmater.7b02563 Chem. Mater. 2017, 29, 7078−7082