Comment on "Observation of substitutional site preference in a quasicrystal and implication on local structure"
نویسندگان
چکیده
A combination of magnetic susceptibility and Mossbauer measurements on quasicrystalline i Ah4Mn2o-xFexSi6 (0.02 ~ x ~ 7.5) establishes that Mn atoms in i-Ab4Mn2oSi6 occupy two distinct classes of sites, and that Fe substitutes for only one of them. The two classes are distinguished by the possession or otherwise of a localized magnetic moment. The data are consistent with a structure of in terconnecting Mackay icosahedra (MI) in which localized moments are possessed only by Mn atoms ad jacent to "broken" MI connections. The implied connectivity of the resulting MI network is close to that anticipated for a packing of MI on a three-dimensional Penrose-tile lattice.
منابع مشابه
Rhombellanic Crystals and Quasicrystals
Design of some crystal and quasicrystal networks, based on rhombellane tiling,is presented. [1,1,1]Propellane,is a synthesized organic molecule; its hydrogenated form, the bicyclo[1.1.1]pentane,may be represented by the complete bipartite graph K2,3 which is the smallest rhombellane. Topology of translational and radial structures involving rhombellanes is described in terms of vertex symbol, c...
متن کاملDelay-dependent stability for transparent bilateral teleoperation system: an LMI approach
There are two significant goals in teleoperation systems: Stability and performance. This paper introduces an LMI-based robust control method for bilateral transparent teleoperation systems in presence of model mismatch. The uncertainties in time delay in communication channel, task environment and model parameters of master-slave systems is called model mismatch. The time delay in communicatio...
متن کاملRethinking the Theory of Change for Health in All Policies; Comment on “Health Promotion at Local Level in Norway: The Use of Public Health Coordinators and Health Overviews to Promote Fair Distribution Among Social Groups”
This commentary discusses the interesting and surprising findings by Hagen and colleagues, focusing on the role of the public health coordinator as a Health in All Policies (HiAP) tool. The original article finds a negative association between the employment of public health coordinators in Norwegian municipalities and consideration of a fair distribution of social and economic resources betwee...
متن کاملLow Decision Space Means No Decentralization in Fiji; Comment on “Decentralisation of Health Services in Fiji: A Decision Space Analysis”
Mohammed, North, and Ashton find that decentralization in Fiji shifted health-sector workloads from tertiary hospitals to peripheral health centres, but with little transfer of administrative authority from the centre. Decisionmaking in five functional areas analysed remains highly centralized. They surmise that the benefits of decentralization in terms of services and outcomes will be limited....
متن کاملThe Far Right Challenge; Comment on “The Rise of Post-truth Populism in Pluralist Liberal Democracies: Challenges for Health Policy”
Speed and Mannion make a good case that the rise of populism poses significant challenges for health policy. This commentary suggests that the link between populism and health policy should be further nuanced in four ways. First, a deconstruction of the term populism itself and a focus on the far right dimension of populist politics; second, a focus on the supply side and more specifically the ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Physical review letters
دوره 61 7 شماره
صفحات -
تاریخ انتشار 1987