World

Dear CRYSTALlers,

The Theoretical Chemistry Group of the University of Torino and the Department of Chemistry and the Thomas Young Centre at Imperial College London are organising the

MSSC2025 Summer School on Ab initio Modelling in Solid State Chemistry

to be held in Torino (Italy), 8-12 September 2025. The School is designed for Master and Ph.D. students, as well as for post-docs and researchers who have an interest in getting or strengthening a background in Computational Solid State Chemistry, Physics, Materials Science, Surface- and Nano-Science.

The week-long School consists of morning lectures and afternoon hands-on tutorial sessions, where the formal framework and functionalities of the CRYSTAL electronic structure package will be explored.

Registration opens on March 15 2025. See the School website for further details.

The School takes place in the elegant city of Torino (Italy):

­
While we strongly encourage in-person participation, we also offer the possibility to attend remotely through streaming of morning lectures and afternoon hands-on tutorials.

Participants will have the opportunity to present their research at a poster session.

See you in Torino!

Dear code developers',

I am currently working on optical materials for optoelectronic device applications using CRYSTAL code. However, I have been unable to find any input files or methods for calculating photon energy (or frequency) versus optical parameters, such as the real and imaginary parts of the dielectric constant, refractive index, extinction coefficient, or optical absorption coefficient.

While reviewing several research articles, I did not come across any studies where optical properties were calculated using the CRYSTAL code.

Therefore, I would like to ask: Is it possible to calculate photon energy vs. optical parameters using the CRYSTAL code? If so, I would greatly appreciate any guidance on how to set up the input file for such calculations.

Thank you in advance for your help!

Best regards,
R. Zosiamliana
Physical Sciences Research Center (PSRC)
Pachhunga University College
Mizoram, India

When calculating the elastic constants (Cij​) for bulk materials, the output values are provided in units of GPa. However, when generating a [0 0 1] surface slab (2D) from the corresponding bulk material using the SLABCUT keyword, the output elastic constant (Cij​) values are given in Hartree (Ha).

Could anyone please clarify whether these values are expressed in Ha/Bohr² or Ha/Ų, considering that the conventional SI unit for surface (Cij) in 2D materials is N/m?

here is my output comparison between bulk and 2D surface

For Bulk
SYMMETRIZED ELASTIC CONSTANTS FOR CUBIC CASE, IN GPa

| 121.241 47.439 47.439 0.000 0.000 0.000 |
| 121.241 47.439 0.000 0.000 0.000 |
| 121.241 0.000 0.000 0.000 |
| 71.165 0.000 0.000 |
| 71.165 0.000 |
| 71.165 |
For 2D-surface
SYMMETRIZED ELASTIC CONSTANTS FOR TRICLINIC CASE, IN HARTREE

| 2.059 0.349 0.000 |
| 2.059 0.000 |
| 1.099 |

Thank you for the forum and responses. I have a typical problem for a rather simple mixed ionic/covalent system comprised of Na, Si and O only. Simple system but SCF convergence is not. Of note, I really like the presence of built-in basis sets and use them exclusively. I am running EOS (and not only) with cam-B3LYP/potTZVPrev2 built-in basis set. SCF starts converging to some 10-6 and then it starts oscillating. It is very typical of my medium-level CRYSTAL user attempts and expertise. it is an insulating state, with a bandgap of 10 eV, so no funny conductive state convergence problems. None of my attempts to use LEVSHIFT, NODIIS and FMIXING make it to converge to TOLDEE of 7 (or in EOS case to 8). Raising LEVSHIFT just leads to conducting state eventually and calculation does not converge. I understand that this is a triple zeta basis set but since it is built in and presumably balanced and robust, I was hoping it would lead to convergence somehow.

input.d12

Dear all, I am running EOS calculation with pre optimization. I specify

EOS
RANGE
0.92 1.08 8
PREOPTGEOM
MAXCYCLE
500
END
BASISSET
mTZVP 
DFT
B973C
XLGRID
END

and it registers

INFORMATION **** MAXCYCLE **** MAXIMUM NUMBER OF OPTIMIZATION CYCLES         500

but then at some point in time preoptimization fails after 102 cycles only.

CONVERGENCE TESTS UNSATISFIED AFTER 102 ENERGY AND GRADIENT CALCULATIONS

******************************************************************
* OPT END - FAILED    * E(AU):  -6.954164500406E+03  POINTS  102 *
******************************************************************

I am running a rather simple crystal Na2Si2O5 with B973C and mTZVP . When calculation begins, I immediately get

ERROR **** CHOLSK **** BASIS SET LINEARLY DEPENDENT

This is strange since I already used B973C and mTZVP in other situations and it worked. This one seems random. Plus this basis set is built in and mandated to be used with B973C. Why is it linearly dependent and how to circumvent that?

thank you

Colleagues, I am looking for a procedure to calculate anharmonic shifts for C-H vibrations in molecular crystal. What if I have several C-H linkages, e.g. is there a way to automate this process for a large molecule or each C-H bond anharmonicity needs to be calculated in a separated calculation? Thank you

I am getting multiple imaginary frequencies due to methyl rotational modes.
I tried different functional/basis set and tightening the geometry optimization convergence but still imaginary frequencies persistently appear. What other options might solve the imaginary frequency issue?

I am using the script file below to submit crystal23 jobs in a cluster, and I would like to know a way to set the output filename in this script. Also, I would like to see the temporary content of the output file in my $PBS_O_WORKDIR directory. Is there a simple way to do that?
In the way it is now, the output is going to the runerr file in the $PBS_O_WORKDIR directory, and only at the end of the calculation.
The working directory is set to $CRY23_SCRDIR/$PBS_JOBID where the $SCRDIR = /work/ppiquini

#!/bin/bash
### Name of the execution queue ###
#PBS -q testes
#PBS -N test33
#PBS -o runout
#PBS -e runerr
#PBS -l nodes=1:ppn=4
#
module load openmpi/4.1.1-gcc-9.4.0
#
cd $PBS_O_WORKDIR
echo "-----------------------------------------"
echo "beginning of the job:" `date`
echo $PBS_O_WORKDIR
#
source $HOME/CRYSTAL23/utils23/cry23.bashrc
mkdir -p $CRY23_SCRDIR
cp $PBS_JOBNAME".d12" $CRY23_SCRDIR/INPUT
cd $CRY23_SCRDIR
#
mpirun -np 4 $CRY23_EXEDIR/$VERSION/Pcrystal 
#
cd /work/ppiquini
rm -r ./$PBS_JOBID
echo "Final do job:" `date`
echo "-----------------------------------------"

Dear users
Please i need help to install the CRYSTAL17 Parallel execution. The serial sequence that i have previously installed works well.
Many thanks in advance

Hello,
I have completed the frequency calculation at room temperature. How can I restart the calculation with a different temperature while everything else is kept unchanged?

Many people today are wondering: "What is a spin current?". While the question may seem legitimate, experts in the field might quip, "Well, of course, it's a current of spin, you dummy!" So, rather than focus on what a spin current is, I find it more interesting to ask: "Why is the spin current so important?"

This is precisely what we explored in our letter titled "Unveiling the Role of Spin Currents in the Giant Rashba Splitting of Single-Layer WSe2." WSe2 (tungsten diselenide) belongs to the class of transition metal dichalcogenides (TMDs). In their monolayer form, TMDs have attracted significant interest due to their exotic physical properties and potential applications in spintronics. For example, the combination of space inversion symmetry (SIS) breaking, time-reversal symmetry (TRS) preservation, and strong spin−orbit coupling (SOC) leads to a giant Rashba-type I spin splitting at the top of the valence band in single-layer TMDs—ranging from 150 to 500 meV at the K point.

Traditional Density Functional Theory (DFT) underestimates Rashba splitting due to the fact that the DFT Hamiltonian does not include SOC. Trying to incorporate SOC explicitly in the Hamiltonian leads to spin-current DFT (SCDFT), where the energy functionals E[n, Jx, Jy, Jz] (n, being the particle number density) depend on the noncollinear spin-current components Jx, Jy and Jz. In this letter we have tested two ways of extending DFT to SCDFT in order to properly capture the modifications to the electronic band structure of single-layer WSe2 due to SOC:

• An explicit inclusion with the meta-generalized-gradient approximation functional (MGGAs) J-r2SCAN;
• An implicit inclusion with the use of the hybrid PBE functional with a fraction of exact exchange.

Our findings reveal that the systematic underestimation of Rashba splitting in the valence band—by about 15%—can be attributed to the absence of spin currents in traditional DFT. Indeed, SCDFT increases the Rashba splitting by 18–20%, aligning well with experimental values of 513 ± 10 meV. Additionally, SCDFT improves the description of quasi-degenerate band gaps at KK and KQ, as well as the gap at GammaK.

In summary, we’ve demonstrated that spin currents are essential for accurately modeling SOC effects in 2D materials. SCDFT effectively resolves the Rashba splitting underestimation, positioning it as a superior alternative to standard DFT for spintronic materials. While hybrid functionals yield better band gap predictions, meta-GGA functionals that explicitly include spin currents enhance SOC accuracy. Future work will focus on combining the strengths of both SCDFT approaches.

If you’d like to read the full letter, you can find it here:
https://pubs.acs.org/doi/abs/10.1021/acs.jpclett.4c01607

All calculations were performed using the CRYSTAL software. If you’re curious about visualizing spin currents, you can explore their beautiful swirls using the dedicated class available in the CRYSTALClear python framework:
https://github.com/crystaldevs/CRYSTALClear

I am trying to run a SOC calculation on some oxides. I first ran a non SOC calculation, optimizing the structure. It converged normally. After that I created the following input file, to include the spin-orbit coupling contribution:

XXX
SLAB
1
12.69372704  12.68784779  120.044058
32
235    -3.586064252172E-04  1.785780347880E-01  1.434019668017E+00
235     4.993953039180E-01  1.784529984229E-01  1.438839678176E+00
...
ENDGEOM
235 5
STUTSC
0 0 10 2.0 1
 9659.390000   -0.000371
...
99 0
ENDBASIS
TWOCOMPON
SOC
ENDTWO
DFT
SPIN
XXLGRID
PBE0
ENDDFT
SHRINK
24 24
TOLINTEG
8 8 8 8 30
SPINLOCK
0 50
ATOMSPIN
8
15 +1
16 +1
19 +1
20 +1
13 -1
14 -1
17 -1
18 -1
MAXCYCLE
400
FMIXING
60
SMEAR
0.001
ENDSCF

However, I am getting the following message at the output

 CYC   0 ETOT(AU) -1.055244791621E+04 DETOT -1.06E+04 tst  0.00E+00 PX  1.00E+00
 TTTTTTTTTTTTTTTTTTTTTTTTTTTTTT FDIK        TELAPSE     5489.51 TCPU     5471.81
 ERROR **** ZERO **** FERMI ENERGY NOT IN INTERVAL

Since it is the first time I am using the SOC, I would like to known if I am doing something wrong or if is there a way to circumvent this SCF issue.

Let's start this section

Is there a way to tell from the .out if the calculation was performed either in the SCDFT or the SDFT formalism?

CRYSTALClear is an open source project that provides an easy Python interface with CRYSTAL. The package allows you to quickly extract information from the CRYSTAL output files and to easily generate customizable plots of computed quantities. In particular, the package supports plotting functionalities for:

Band Structures and DOSS	Mechanical Properties	IR and Raman Spectra

QTAIM	Transport Properties	Density Maps

For a more comprehensive review of the package capabilities we refer you to the Documentation Website.

How to Install

Prerequisites:

• Python: Ensure you have Python installed on your system.

• conda (Optional but Recommended): conda is a powerful package and environment manager that simplifies the process of managing Python dependencies. If you don't have conda, install it from the official Anaconda distribution: https://www.anaconda.com/

Installation Steps:

1. Create a Dedicated Environment (Recommended):
   Creating a separate conda environment for CRYSTALClear helps isolate its dependencies from other projects and avoid potential conflicts.

conda create -n env_name python=3.9  # Replace 3.9 with your desired Python version

2. Activate the Environment (Reccommended):

conda activate env_name

3. Install CRYSTALClear using pip:

pip install CRYSTALClear

      This command will install the CRYSTALClear library and its dependencies.

Verification:

• Check Installation:
  After installation, you can verify the installation by importing the library in a Python script or interactive session:

import CRYSTALClear 

      If the import is successful without any errors, the installation was successful.

Additional Notes:

• Dependencies: The CRYSTALClear library might have dependencies on other libraries. pip will automatically install these dependencies during the installation process.
• Updating: To update the CRYSTALClear library to the latest version:

pip install --upgrade CRYSTALClear

Troubleshooting:

• If you encounter any issues during installation:
  • Check for any error messages and try to resolve them based on the error descriptions.
  • Ensure you have an active internet connection.
  • Try updating pip to the latest version: pip install --upgrade pip
  • If the issue persists, consider creating a new conda environment and reinstalling the library.

If you the issues persist please feel free to comment here below we will try our best to help you.

How to Use it

In order to use any of the feature available in the package the user need to generate
a CRYSTAL object through the crystal_io module. Three classes are available to the user
for different use cases:

1. Crystal_output: To extract informations and generate the object required to plot
   from any .out file of the CRYSTAL package.
2. Properties_output: To generate the objects required to plot any of quantities
   stored in the .DAT and .f25 files generated by the PROPERTIES module.
3. External_unit: To generate the objects required to plot any of the quantites stored
   in .DAT and .f25 file generated by CRYSTAL.

Once the object is generated the user can generate the desired plot using the functions
in the plot module

Example

   # Example Band Structure plot
   from CRYSTALClear.crystal_io import Properties_output
   import CRYSTALClear.plot as CCplt
   import matplotlib.pyplot as plt

   data = Properties_output().read_electron_band()
   CCplt.plot_electron_band(data, **kwargs) # see the documentation for the available **kwargs 

   # The plotting function returns a matplotlib object that can be visualized as follows
   plt.show()

The plotting function will return one (or a list of) matplotlib object(s) that the user can easily modify as any other plot produced with the library.

For a more comprehensive set of example we refer you to the following jupyter notebook repository.

How to Contribute

Any contribution to the project is more than welcome and greatly appreciated, given the open source nature of the project. If you'd like to do so, please check our guidelines on GitHub

How to Cite

If you use this package in any of your work we kindly ask you to cite the following pubblication:

Camino, Bruno, Huanyu Zhou, Eleonora Ascrizzi, Alberto Boccuni, Filippo Bodo, Alessandro Cossard, Davide Mitoli, Anna Maria Ferrari, Alessandro Erba, and Nicholas M. Harrison, Comput. Phys. Commun. 292, 108853 (2023).

@article{camino2023crystalpytools,
  title={CRYSTALpytools: A Python infrastructure for the CRYSTAL code},
  author={Camino, Bruno and Zhou, Huanyu and Ascrizzi, Eleonora and Boccuni, Alberto and Bodo, Filippo and Cossard, Alessandro and Mitoli, Davide and Ferrari, Anna Maria and Erba, Alessandro and Harrison, Nicholas M},
  journal={Computer Physics Communications},
  volume={292},
  pages={108853},
  year={2023},
  publisher={Elsevier}
}

Welcome to the official forum for CRYSTAL software users! This is a space to share knowledge, find support, and connect with others interested in solid-state simulations. To maintain a productive and respectful environment, we ask all members to adhere to the following rules:

1. Be Respectful and Professional

Treat all members with courtesy and respect.
Avoid using offensive, discriminatory, or inflammatory language.
Critique ideas, not people.

2. Stay On-Topic

Ensure your posts are relevant to CRYSTAL software, solid-state simulations, or related topics.
Avoid spamming, advertising, or self-promotion unrelated to the forum’s purpose.

3. Use Clear and Specific Titles ️

Summarize your question or discussion topic in the post title.
Avoid vague titles like "Help needed" or "Question."

4. Provide Context and Details ️

When asking for support, include:
A clear description of the issue.
Relevant input/output files or error messages (as text or attachments, not screenshots).
Your system configuration and code version (i.e., CRY23-MPP, CRY17,...).
Avoid posting confidential or sensitive data.

5. Avoid Duplicate Posts

Use the search function to check if your question has already been answered.
If a similar thread exists, contribute to it instead of starting a new one. 🧵

6. Follow Technical Posting Guidelines

Use code blocks or formatting tools for any code and error message.
Ensure attachments are in accepted formats (.d12, .d3, .out., .outp, .dat, .png, .jpg, .txt).

7. No Unauthorized Sharing of Software or Licenses

Do not share CRYSTAL software or any other proprietary content.
Discussions about bypassing licensing restrictions are strictly prohibited.

8. Moderation and Reporting ️

Moderators reserve the right to edit, move, or delete posts that violate these rules.
If you see inappropriate content, report it.

9. Keep the Community Inclusive

Encourage and support new users.
Avoid gatekeeping or discouraging questions from beginners.

10. Follow Legal and Ethical Guidelines ️

Ensure your contributions comply with copyright laws and ethical standards.
Cite sources where applicable.

The CRYSTAL code will have a dedicated full day at the upcoming Graduate School on Electronic Structure Theory at STFC Daresbury Laboratory, taking place 24–28 February 2025!

This event is a great opportunity to:

• Dive deep into the fundamentals of electronic structure theory.
• Gain hands-on experience with CRYSTAL, alongside other leading software packages like CASTEP and QUESTAAL.
• Learn both command-line and ASE (python based) interfaces.
• Connect with peers and experts in the field.

Whether you're a doctoral researcher, postdoc, or someone looking to enhance your expertise in electronic structure codes, the dedicated CRYSTAL day offers a valuable opportunity to develop a solid understanding of the code's features, gain practical experience, and understand how it fits into the broader landscape of computational tools.

Event Details
Dates: 24-28 February 2025
Application deadline: 19 January 2025.
Venue: Science and Technology Facilities Council, Daresbury Laboratory, UK.
Apply Now: https://ccp9.ac.uk/graduate_school_2025/

Take advantage of this opportunity to expand your knowledge and experience with the CRYSTAL code in a collaborative and dynamic environment. We look forward to seeing you there!