Acronym shadow
Name small heptagrammic disphenoid,
small heptagramm atop fully orthogonal small heptagramm
Circumradius sqrt[1+1/(2 sin2(2 pi/7))]/2 = 0.674163
Confer
more general:
{n/d} || perp {n/d}  
general polytopal classes:
segmentotera   scaliform   noble  

Incidence matrix according to Dynkin symbol

xo7/2oo ox7/2oo&#x   → height = sqrt[1-1/(2 sin2(2pi/7))] = 0.426636
({7/2} || perp. {7/2})

o.7/2o. o.7/2o.    & | 14 |  2  7 | 1 21 |  8 14 |  9
---------------------+----+-------+------+-------+---
x.   .. ..   ..    & |  2 | 14  * | 1  7 |  7  7 |  8
oo7/2oo oo7/2oo&#x   |  2 |  * 49 | 0  4 |  2  4 |  4
---------------------+----+-------+------+-------+---
x.7/2o. ..   ..    & |  7 |  7  0 | 2  * |  7  0 |  7  {7/2}
xo   .. ..   ..&#x & |  3 |  1  2 | * 98 |  1  2 |  3
---------------------+----+-------+------+-------+---
xo7/2oo ..   ..&#x &   8 |  7  7 | 1  7 | 14  * |  2
xo   .. ox   ..&#x     4 |  2  4 | 0  4 |  * 49 |  2
---------------------+----+-------+------+-------+---
xo7/2oo ox   ..&#x &   9 |  8 14 | 1 21 |  2  7 | 14

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