ORCA hands-on workshop

ORCA Hands-on Workshop

  • Date: May 21-22, 2024
  • Venue: Institute of Materials and Machine Mechanics, Slovak Academy of Sciences in Bratislava
  • Format: F2F
  • Hands-on training
  • Free participation
  • For academic users only
  • Registrácia je otvorená do 16. mája 2024

National Competence Centres for HPC in NCC Slovakia and NCC Poland are collaborating to organize a 2-day workshop on ORCA program package. ORCA. ORCA provides cutting-edge capabilities in the fields of density functional theory and correlated wave-function based methods. It offers an interesting alternative to other computational chemistry packages. Participants will learn the basics of work with ORCA and get a hands-on experience with the most common types of calculations (properties, geometry optimization, spectroscopy, relativistic corrections). Moreover, participants can submit their own use cases or problems that can be addressed and discussed on the second day of the event.

The workshop will take place in Bratislava, in F2F format. The event will be held in English. Participants from the whole EuroCC network are welcome!

Only participants from academic institutions are eligible to attend.

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ORCA is a multi-purpose quantum chemistry software package. It features a wide variety of methods ranging from semi-empirical methods, density functional theory to correlated single- and multi-reference wave function-based methods. Environmental as well as relativistic effects can be taken into account. Orca features leading software tools in the calculation of molecular properties, and offers a native molecular dynamics module as well as a native QM/MM module for large-scale systems. It is a powerful and versatile quantum chemistry software package, primarily developed by the group of Prof. Frank Neese. It is free for academic use, licenses (including commercial) are available through FACCTs.


Day 1: Introduction to ORCA and Basic Usage

Session 1: Introduction to ORCA

9:00 AM – 9:30 AM Registration and Welcome

9:30 AM – 10:00 AM Overview of High-Performance Computing (HPC) in Computational Chemistry

10:00 AM – 10:45 AM Introduction to the ORCA Package: Features and Capabilities

10:45 AM – 11:00 AM Break

Session 2: Installation and Setup

11:00 AM – 11:30 AM HPC cluster setup 

11:30 AM – 12:00 AM Installing ORCA on HPC Systems: Best Practices and Considerations

12:00 AM – 12:30 PM SLURM scheduler and first computation in ORCA

12:30 PM – 1:30 PM Lunch Break

Session 3: Basic Computations with ORCA

1:30 PM – 2:15 PM Input File Structure and Syntax: Getting Started with ORCA

2:15 PM – 3:00 PM Running Basic Quantum Chemistry Calculations

  • Single point energy 
  • Geometry Optimization

3:00 PM – 3:15 PM Break

Session 4: Analyzing ORCA Oputput

3:15 PM – 4:00 PM Analyzing ORCA Output: Extracting Useful Information and Plotting Results

4:00 PM – 4:30 PM Q&A and Wrap-Up of Day 1

Day 2: Advanced Computations and Scalability

Session 1: Advanced Computations with ORCA

9:00 AM – 10:30 AM Advanced Input Options:

  • Vibrational frequencies
  • Including Solvation Effects
  • Solvent modeling methods
  • Relativistic corrections
  • Spectroscopy (Raman and NMR calculations) 

10:30 AM – 10:45 AM Break

Session 2: Scalability of Computations

10:45 AM – 11:30 AM Understanding Scalability Metrics: Weak and Strong Scaling. Strategies for Improving Performance and Efficiency on HPC Systems

11:45 AM – 12:30 PM Evaluating Scalability of ORCA Computations – Practical Exercise

12:30 PM – 1:30 PM Lunch Break

Session 3: Case studies 

1:15 PM – 2:00 PM Calculations of redox potentials

2:00 PM – 2:45 PM Case studies prepared according to participants’ submissions 

2:45 PM – 3:00 PM Break

Session 4: Troubleshooting and best practices

3:00 PM – 4:00 PM Computational troubleshooting and best practices

4:00 PM – 4:30 PM Q&A and Wrap-Up of training


After the registration you'll receive a registration confirmation email. (If you haven't received the confirmation email, please check your spam folder.)

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    The event will take place in the premises of the Institute of Materials and Machine Mechanics (Slovak Academy of Sciences) in Bratislava.

    Address: ÚMMS SAV, v. v. i. Dúbravská cesta 9/6319 845 13 Bratislava
    DD: 48.170532, 17.068432
    DMS: N 48° 10′ 13.916”, E 17° 4′ 6.355”
    Google Maps

    The workshop is free for registered participants. Light meals and coffee breaks will be provided by the local organizers.

    You will need your own laptop to be able to participate in the hands-on parts. HPC system Devana will be used for the workshop. Access information and instructions will be provided shortly before the workshop.


    BY PLANE: Bratislava Airport (BTS)

    There are direct flights to a number of destinations in Europe and a number of airlines operate their direct routes to Bratislava. Bratislava airport can be reached from the city centre in 15–20 minutes. To get to the city center you can take a taxi – do not forget to ask about the price in advance or use HOPIN mobile app. If you travel on the budget,  take the bus no. 61 to the main train station. From here, you can walk to the city centre in 15 minutes or take bus no 93 (exit Hodžovo námestie) or tram no 1 (exit Námestie SNP). Bus tickets are available from ticket machines at bus stops or in kiosks. The tickets which cost around EUR 1 must be validated in the buses.

    BY PLANE: Vienna – Schwechat Airport (VIE)

    The airport at Vienna-Schwechat is only 40 kilometres west of Bratislava and it is one of the main gateways to Slovakia. Buses to Bratislava depart at 30 to 60-minute intervals. Tickets can be bought on the bus; chceck the following companies slovaklines.sk, regiojet.com, flixbus.com.

    BY TRAIN: ZSSK – Slovak National Carrier

    Bratislava connects to the main lines from Prague, Budapest, Vienna and various regions in Slovakia. The Bratislava Main Station is well connected to the rest of the city via trams, buses or trolleybuses and you can get to the Old Town on foot in only 15 minutes. From the train station in Petržalka, the no. 80, 91, 93 buses take you to the city centre.

    BY TRAIN: RegioJet

    The RegioJet carrier provides connection to Prague, Brno and Pardubice.

    BY BUS:

    Bratislava is also conveniently connected with many European cities via a network of bus lines. It has frequent service to the surrounding areas and also to other regions in Slovakia. Buses arrive and depart from Mlynské Nivy bus station. Coaches between Bratislava and Vienna run at one-hour intervals.

    Useful links:




    BY CAR:

    Bratislava is situated at the intersection of several important motorways. The distance to Prague is 330 km, Budapest 200 km and Vienna 65 km. If you are bringing your own car, you need to have a valid electronic vignette to use the specified sections of motorways and expressways. The vignette is related to a specific time period regardless of the distance driven or the number of journeys. The minimum validity period is ten days (costs around EUR 10). HERE.

    Information sourced from visitbratislava.com where you can find plenty more useful tips for getting around Bratislava.


    Diverse hotels, hostels, guest houses and private accommodation can be booked via standard providers – check e. g. Trivago or booking.com.

    There are a few hotels near the faculty:
    Hotel Sorea Regia
    How to get from the hotel to the venue? => From the hotel take bus number 37 from the stop Kráľovské údolie to the stop Patrónka, then walk for 13 minutes.

    Hotel Devin
    How to get from the hotel to the venue? => From the hotel take bus number 37 from the stop Most SNP to the stop Patrónka, then walk for 13 minutes.

    Grand Hotel River Park
    How to get from the hotel to the venue? => Take bus number 37 from the stop Kráľovksé údolie to the stop Patrónka, then walk for 13 minutes.

    Hotel Družba
    Hotel Družba is a budget accomodation for students. From the hotel take bus number 37 from the stop Lafranconi to the stop Patrónka, then walk for 13 minutes.


    ORCA tutorials – Compatible with ORCA 5.0! — ORCA tutorials 5.0 documentation (orcasoftware.de)