Vous avez cherché: trigonal (Anglais - Portugais)

trigonal crystal system
sistema cristalino trigonal

in the trigonal case there also exists a space group p3112.
no caso trigonal existe também um grupo de espaço p3112.

tetragonal, trigonal and hexagonal minerals can only show two colors and are called dichroic.
os cristais dos sistemas tetragonal, trigonal e hexagonal podem apenas exibir duas cores e dizem-se dicróicos.

==structure and bonding==the geometry of a molecule of bf3 is trigonal planar.
the geometry of a molecule of bf3 is described as trigonal planar.

bi2te3 cleaves easily along the trigonal axis due to van der waals bonding between neighboring tellurium atoms.
2te3 cleaves easily along the trigonal axis due to van der waals bonding between neighboring tellurium atoms.

the trigonal or triangular pyramid with all equilateral triangles faces becomes the regular tetrahedron, one of the platonic solids.
uma pirâmide de base triangular é chamada de pirâmide triangular (ou tetraedro).

one of the causes of pain in the posterior ankle region with forced plantar flexion is an acute plantar flexion injury, leading to fracture of the trigonal process and damages to the trigonal synchondrosis.
uma das causas de dor na região posterior do tornozelo na flexão plantar forçada é a lesão aguda na flexão plantar, levando à fratura do processo trigonal e a danos na sincondrose trigonal.

with the implantation of this ring, the posterior cusp is brought closer to the anterior cusp in the anteroposterior direction, without interfering in the transversal diameter inter-trigonal.
na implantação deste anel, aproximam-se as cúspides posteriores da anterior no sentido ântero-posterior, não interferindo no diâmetro transverso intertrigonal.

:in the international short symbol the first symbol (31 in this example) denotes the symmetry along the major axis (c-axis in trigonal cases), the second (2 in this case) along axes of secondary importance (a and b) and the third symbol the symmetry in another direction.
:no símbolo internacional o primeiro símbolo (31 neste exemplo) denota a simetria ao longo do eixo principal (eixo-c nos casos trigonais), o segundo (2 neste caso) ao longo de eixos de importância secundária (a e b) e o terceiro símbolo a simetria em outra direção.