Building a Honeycomb Structure in MCNP: Error Solving

[oksuz_]

Hi,

I am trying to build a honeycomb structure in MCNP. The code is given below. Hexagonal lattice
1 0 -1 -19 29 fill=1 imp:n=1
2 1 -2.26 -10 11 -12 13 -14 15 u=1 lat=2 imp:n=1
3 0 1:19:-29 imp:n=0

1 c/z 50 50 200
19 pz 31
29 pz -31
10 px 1
11 px -1
12 p 1 1.7320508076 0 2
13 p -1 1.7320508076 0 2
14 p 1 1.7320508076 0 -2
15 p -1 1.7320508076 0 -2

m1 6012 1
sdef
f1:n 1
nps 2000

However, it keeps giving the error of "Lattice in cell 2 has no fill"

I have come across this document

https://permalink.lanl.gov/object/tr?what=info:lanl-repo/lareport/LA-UR-13-23338

which seems to address the problem, however, it does not give any information about the surface they chose.

Can anyone give suggestion to solve the issue?

Thank you in advance.

 

[Astronuc]

What type of system is one attempting to model/simulate? VVER?

Has one tried using RHP or HEX in input?