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+2(f.T(h k 1)+fyU(h k 1))(S2(h k 1)-Sa(h k 1))sin(1/4) +2(frT(h k 1)+f.U(h k 1))Ss(h k 1)sin(1/4) +f.(T(hk1)+U(hk1))sin(π(h+)/2)〕2}, where u is a constant and laillaalla,1=8(6+2 )a. (1) If taken,in formula (1),fr=23,f.=28,and b=(v6-v2 )/2,then FT patterns of the model along different "symmetry diretions"are shown in Fig.3.(a)-(c),respectively.Diffraction sports are shown as circles whose diameter are propotional to diffration intensites.And the sports whose inten- sites are less than 0,041 (0,0,0)are omitted.These patterns are astonishingly similar to the EDPsc1,of VNi alloy in practice.Additionally if taken a= 0,54nm,then the volume of the unite primitive cell of the model is 2.086nm x 2,086nm x1.118nm.The bonding length L between two neighbouring atoms satisfies ineqality 0,24nm<0.31nm.Therefore the atomic structure pre- sented here may exist cr will appear in the real word. 12d 888888888 -12a 888688过: 99?9e999? (@)g8g888888 8888888885 9999999994总F 000000000 (b)666666666 器: 888888888 (a) Fig.3 Fourier transforms in a plance (a)orthogonal to the "twelvefold axis " (b)o"thogonal to the twofold axis,and (c)differing 30 in orientation. (In fact,pattern (c)is in a zone where h/k satisfies the inequality -0.60<h/k<-0.57for-38<k<38and-38<h<38 cxcept点=0) The authors would like to point out that this symmetry is not,in fact, twelvefold symmetry in mathematical sense but this symmetry is very close to twelvefo'd symmetry in practice.On the other hand,the authors arc also not sure if the EDPs(1>of V60Ni4)alloy has twelvefold symmetry in strictly sense.The authers thin'that Dr.Pauling's opinion'about quasicryistal shculd not been largely ignored,On the other hand,if we appropriately chang the distributions of atoms V and Ni or chang the dimension cf b in T polyhedron show in Fig.1.(a)and (b),FT patterns of structure models can 294〔 。 几 及 了 掩 几 冷 一 吞 二 人 吞 。 〔 ‘ 。 为 吞 二 。 儿 左 二 吞 〕 , 曰 知 一与 每 声 厂 。 川 。 川 二 了 了 。 , 轰 , , , 。 , 侧 一 召 , , “ ,, 一 , , , 〔 ’ 。 , 。 火 。 · 丁 。 百 。 ‘ 月 读 笼 住 呈 妞 厂 , “ 王 五 呈 ” 丈 , 主 。 主 玉 , 一 。 的 乃 吞 一 。 盯 盆 人 及 五 王 · 儿 一 人 二 五 , , 住 , , 几 、 ’ 、 丁川 , , 〔 ” 三注, , · 丫 ’ 飞, · 尸 〔 ’ 〕 少 · 〔 ” 〕 , , 卜 手 从 · ·
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