### dipole and band structure

Posted:

**Wed May 15, 2019 8:53 am**Dear Yamboers,

I am trying to extract the transition dipole matrix elements (in the simplest IP-RPA approximation) along a specific path in the brilloiun zone. Since the code requires a uniform grid to perform calculation, I wonder how I can get Yambo to at least include such points.

I tried to use ypp -k k to generate a larger uniform grid including the bands k points, but only a few of them are included in the output. (By the way, is there a way to redirect the output from terminal to file? I tried several operators, namely >, >>, >&, 2>& but none worked. The file is always empty.)

Therefore I tried to use ypp -s b to perform some kind of interpolation, obviously without any QP energy database, but I get this error message:

<---> [INTERPOLATION] Errors: Max, Avg, Avg_rel = 9.44733620E-06 1.21712606E-06 5.77973924E-06At line 612 of file mod_com.f90

Fortran runtime error: End of record

These are the inputs for the two test runs, respectively:

ypp -k k:

ypp -s b

Is this somehow doable? What am I missing?

Thank you in advance,

I am trying to extract the transition dipole matrix elements (in the simplest IP-RPA approximation) along a specific path in the brilloiun zone. Since the code requires a uniform grid to perform calculation, I wonder how I can get Yambo to at least include such points.

I tried to use ypp -k k to generate a larger uniform grid including the bands k points, but only a few of them are included in the output. (By the way, is there a way to redirect the output from terminal to file? I tried several operators, namely >, >>, >&, 2>& but none worked. The file is always empty.)

Therefore I tried to use ypp -s b to perform some kind of interpolation, obviously without any QP energy database, but I get this error message:

<---> [INTERPOLATION] Errors: Max, Avg, Avg_rel = 9.44733620E-06 1.21712606E-06 5.77973924E-06At line 612 of file mod_com.f90

Fortran runtime error: End of record

These are the inputs for the two test runs, respectively:

ypp -k k:

- Code: Select all
`bzgrids # [R] BZ Grid`

K_grid # [R] K-grid analysis

#NoWeights # Do not print points weight

cooIn= "rlu" # Points coordinates (in) cc/rlu/iku/alat

cooOut= "rlu" # Points coordinates (out) cc/rlu/iku/alat

ListPts # List the internal q/k points also in the parser format

ExpandPts # Expand the internal q/k points in the BZ

%GWKpts # K points list

0.0000000 | 0.0000000 | 0.0000000|

0.0250000 | 0.0000000 | 0.0000000|

... list of the rest of k-point in the path

ypp -s b

- Code: Select all
`electrons # [R] Electrons (and holes)`

bnds # [R] Bands

cooIn= "rlu" # Points coordinates (in) cc/rlu/iku/alat

BANDS_steps=20 # Number of divisions

% INTERPGrid

-1 |-1 |-1 | # Interpolation BZ Grid

%

ShellFac= 20.00000 # The bigger it is a higher number of shells is used

GfnQPdb= "none" # [EXTQP G] Database

GfnQP_N= 1

%QPkrange # generalized Kpoint/Band indices

1|144| 1| 20|

%

%BKpts # K points of the bands circuit

0.00000 |0.00000 |0.00000 |

0.50000 |0.00000 |0.00000 | #M

0.33338 |0.33325 |0.00000 | #K

0.00000 |0.00000 |0.00000 |

%

Is this somehow doable? What am I missing?

Thank you in advance,