//14-hedron (or truncated octahedron) with sides 'a'
lc=1;
a=1;
// octahedron's height: h = 3/2*Sqrt(2)*a
//z=0 octahedron's base, which turns in two piramids with square base
Point(1) = {1.5*a,0.5*a,0,lc};
Point(2) = {0.5*a,1.5*a,0,lc};
Point(3) = {-0.5*a,1.5*a,0,lc};
Point(4) = {-1.5*a,0.5*a,0,lc};
Point(5) = {-1.5*a,-0.5*a,0,lc};
Point(6) = {-0.5*a,-1.5*a,0,lc};
Point(7) = {0.5*a,-1.5*a,0,lc};
Point(8) = {1.5*a,-0.5*a,0,lc};

//z = h*1/3
Point(9) = {1*a,1*a,Sqrt(2)/2*a,lc};
Point(10) = {-1*a,1*a,Sqrt(2)/2*a,lc};
Point(11) = {-1*a,-1*a,Sqrt(2)/2*a,lc};
Point(12) = {1*a,-1*a,Sqrt(2)/2*a,lc};

//z = h*2/3
Point(13) = {0.5*a,0.5*a,Sqrt(2)*a,lc};
Point(14) = {-0.5*a,0.5*a,Sqrt(2)*a,lc};
Point(15) = {-0.5*a,-0.5*a,Sqrt(2)*a,lc};
Point(16) = {0.5*a,-0.5*a,Sqrt(2)*a,lc};

//z = -h*1/3
Point(17) = {1*a,1*a,-Sqrt(2)/2*a,lc};
Point(18) = {-1*a,1*a,-Sqrt(2)/2*a,lc};
Point(19) = {-1*a,-1*a,-Sqrt(2)/2*a,lc};
Point(20) = {1*a,-1*a,-Sqrt(2)/2*a,lc};

//z = -h*2/3
Point(21) = {0.5*a,0.5*a,-Sqrt(2)*a,lc};
Point(22) = {-0.5*a,0.5*a,-Sqrt(2)*a,lc};
Point(23) = {-0.5*a,-0.5*a,-Sqrt(2)*a,lc};
Point(24) = {0.5*a,-0.5*a,-Sqrt(2)*a,lc};

//edges
Line(1) = {8,1};
Line(2) = {2,3};
Line(3) = {4,5};
Line(4) = {6,7};
Line(5) = {1,9};
Line(6) = {9,13};
Line(7) = {13,16};
Line(8) = {16,12};
Line(9) = {12,8};
Line(10) = {12,7};
Line(11) = {7,20};
Line(12) = {20,8};
Line(13) = {16,15};
Line(14) = {15,11};
Line(15) = {11,6};
Line(16) = {13,14};
Line(17) = {14,15};
Line(18) = {9,2};
Line(19) = {3,10};
Line(20) = {10,14};
Line(21) = {10,4};
Line(22) = {5,11};
Line(23) = {3,18};
Line(24) = {18,4};
Line(25) = {2,17};
Line(26) = {1,17};
Line(27) = {17,21};
Line(28) = {21,24};
Line(29) = {24,20};
Line(30) = {21,22};
Line(31) = {22,18};
Line(32) = {24,23};
Line(33) = {23,22};
Line(34) = {23,19};
Line(35) = {19,5};
Line(36) = {19,6};
Physical Line("edge") = {16,7,17,13,6,20,8,14,18,5,19,2,1,9,21,10,22,3,15,4,25,26,23,24,12,11,36,35,27,30,31,28,29,32,33,34};

//surfaces
Line(37) = {18,10};
Line(38) = {3,4};
Line(39) = {19,11};
Line(40) = {5,6};
Line(41) = {22,24};
Line(42) = {23,21};
Line(43) = {14,16};
Line(44) = {13,15};
Line(45) = {8,7};
Line(46) = {20,12};
Line(47) = {17,9};
Line(48) = {1,2};
Line(49) = {10,15};
Line(50) = {15,5};
Line(51) = {5,10};
Line(52) = {14,4};
Line(53) = {4,11};
Line(54) = {11,14};
Line(55) = {6,23};
Line(56) = {23,20};
Line(57) = {20,6};
Line(58) = {19,24};
Line(59) = {24,7};
Line(60) = {7,19};
Line(61) = {19,22};
Line(62) = {22,4};
Line(63) = {4,19};
Line(64) = {18,23};
Line(65) = {23,5};
Line(66) = {5,18};
Line(67) = {11,16};
Line(68) = {16,7};
Line(69) = {7,11};
Line(70) = {6,15};
Line(71) = {15,12};
Line(72) = {6,12};
Line(73) = {8,16};
Line(74) = {12,13};
Line(75) = {13,1};
Line(76) = {1,12};
Line(77) = {16,9};
Line(78) = {9,8};
Line(79) = {20,21};
Line(80) = {21,1};
Line(81) = {1,20};
Line(82) = {24,8};
Line(83) = {8,17};
Line(84) = {17,24};
Line(85) = {22,3};
Line(86) = {3,17};
Line(87) = {17,22};
Line(88) = {21,2};
Line(89) = {2,18};
Line(90) = {18,21};
Line(91) = {3,9};
Line(92) = {9,14};
Line(93) = {14,3};
Line(94) = {10,13};
Line(95) = {13,2};
Line(96) = {2,10};
Physical Line("surf") = {37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96};

//planes
Line Loop(97) = {11,-29,32,34,36,4};
Plane Surface(98) = {97};
Line Loop(99) = {13,14,15,4,-10,-8};
Plane Surface(100) = {99};
Line Loop(101) = {22,15,-36,35};
Plane Surface(102) = {101};
Line Loop(103) = {20,17,14,-22,-3,-21};
Plane Surface(104) = {103};
Line Loop(105) = {30,-33,-32,-28};
Plane Surface(106) = {105};
Line Loop(107) = {2,23,-31,-30,-27,-25};
Plane Surface(108) = {107};
Line Loop(109) = {19,21,-24,-23};
Plane Surface(110) = {109};
Line Loop(111) = {24,3,-35,-34,33,31};
Plane Surface(112) = {111};
Line Loop(113) = {16,17,-13,-7};
Plane Surface(114) = {113};
Line Loop(115) = {18,2,19,20,-16,-6};
Plane Surface(116) = {115};
Line Loop(117) = {25,-26,5,18};
Plane Surface(118) = {117};
Line Loop(119) = {1,5,6,7,8,9};
Plane Surface(120) = {119};
Line Loop(121) = {12,-9,10,11};
Plane Surface(122) = {121};
Line Loop(123) = {27,28,29,12,1,26};
Plane Surface(124) = {123};
Physical Surface(125) = {122,98,100,102,106,124,120,114,118,112,104,108,116,110};
Surface Loop(126) = {102, 104, 116, 118, 108, 110, 112, 98, 122, 124, 106, 120, 114, 100};
Volume(127) = {126};
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