mena

CMENAS and Georgia State University Lecture Series. Bridging the Gulf: Patterns in Contemporary story from Kuwait to Oman (November 14, 2024 3:00pm)

Event Begins: Thursday, November 14, 2024 3:00pm
Location: Off Campus Location
Organized By: Center for Middle Eastern and North African Studies


This presentation focuses on the importance of studying contemporary Gulf states. The definition of contemporary in this context considers the period starting from the early 1990s. The reason for this has to do with the collapse of the Soviet Union, regional changes like the invasion of Kuwait and its consequences, and the wider Middle Eastern regional consequences. The presentation also looks at the patterns that emerged in all Gulf states at the same time in different contexts: political, economic, and social.

Mahjoob Zweiri is a professor of contemporary politics and Middle Eastern history with a focus on Iran and the Gulf region. He was the director of the Gulf Studies Center at Qatar University from 2018 to 2024 and the head of the humanities department from 2011 to 2016. Before joining Qatar University in 2010, Zweiri was a senior researcher in Middle Eastern politics and Iran at the Center for Strategic Studies, University of Jordan. From March 2003 to December 2006, he was a research fellow and then director of the Centre for Iranian Studies in the Institute for Middle Eastern and Islamic Studies at Durham University. Zweiri has more than 95 publications in the areas of Iran, contemporary Middle Eastern history and politics, Gulf studies, social sciences in universities of the future, and artificial intelligence’s role in social sciences. In addition to Arabic, he is fluent in Farsi and English. Zweiri is the founder and editor of the *Journal of Gulf Studies*, published by Intellect, and editor of the book series *Contemporary Gulf States*. Currently, he is a visiting professor at the University of Michigan.

Register and attend over Zoom: https://myumi.ch/pkJWz.




mena

Premios Poder Femenino 2024: Yo Dona homenajea a siete mujeres excepcionales en una noche cargada de esperanza y entusiasmo

En la Real Academia de Bellas Artes de San Fernando, una edición más de los premios Poder Femenino festejó el éxito de siete mujeres que, con su trabajo y ejemplo, contribuyen "al progreso de toda la humanidad". Leer




mena

Facebook amenaza con poner Messenger a disposición de los medios

Mientras mantiene Whatsapp 'limpio' de cualquier uso comercial, la compañía de Mark Zuckerberg pretende abrir su chat 'Messenger' a los grandes editores.




mena

Finnomena touts US, India and Vietnam for investment

The US, India and Vietnam are the three main markets worth investing in to reduce the impact of the expected import tariff policy under president-elect Donald Trump, says digital wealth management platform Finnomena.




mena

Stray dog menace grips Vijayawada

Up to 100 dog bite cases reported in city every day, claims Coporators; shortage of kennels hits street dog sterilisation programme, says VMC official




mena

Schleswig-Holsteinischer Landtag stärkt die nordische Zusammenarbeit - Jahrestreffen des Nordischen Rates auf Island




mena

HafeziCapital Expands International Feasibility Study Services to MENA in Key Sectors: Farming, Ports, Education, Hospitals, Infrastructure, and Oil & Gas

HafeziCapital, a leading international consulting firm renowned for its expertise in structuring and conducting in-depth Feasibility Studies, proudly announces the expansion of its International Feasibility Study services to address critical sectors in the Middle East, Asia Pacific, Latin America, and Africa. This strategic initiative is designed to provide a comprehensive analysis of project viability, enabling [PR.com]




mena

Mauslot Slot Machines: Cara Mendapatkan Kemenangan Sering Seperti Seorang Pro

Mauslot Slot Machines: Cara Mendapatkan Kemenangan Sering Seperti Seorang Pro   Mauslot adalah salah satu permainan kasino online yang paling populer di Indonesia. Game slot ini menawarkan kesempatan untuk memenangkan alternatif mauslot  jackpot besar dengan cara yang sederhana. Namun, untuk meningkatkan peluang kemenangan Anda, Anda perlu memahami beberapa strategi dasar. Berikut adalah beberapa tips untuk […]

The post Mauslot Slot Machines: Cara Mendapatkan Kemenangan Sering Seperti Seorang Pro appeared first on DOMINOQQ - DOMINO QQ ONLINE - DOMINO QIU QIU ONLINE.




mena

Situs Sah 2024: RTP Slots Pragmatic Play dengan Kemenangan Gampang

Situs RTP Slots Online dan RTP Slots deposit pulsa yang diperlengkapi beberapa ratus jenis permainan taruhan taruhan MAUPOKER online betul-betul lengkap, Di sini dengan deposit 10 ribu saja kau sudah bisa berpeluang RTP Live buat memenangi jekpot uang sampai beberapa puluh juta rupiah. Tidak hanya itu fasilitas yang disiapkan juga betul-betul lengkap, tidak cuma Siapkan […]

The post Situs Sah 2024: RTP Slots Pragmatic Play dengan Kemenangan Gampang appeared first on DOMINOQQ - DOMINO QQ ONLINE - DOMINO QIU QIU ONLINE.




mena

Trik Bermain Game Slot88 Online Mudah Menang

Permainan taruhan judi londoncallingband.com online tidak hanya bisa dimenangkan dengan mengandalkan keberuntungan. Akan tetapi anda perlu menguasai beberapa trik dan strategi supaya bisa memperoleh kemenangan mudah. Justru suatu kesalahan yang selama ini sering dilakukan oleh para player terutama pemula adalah bermain hanya mengandalkan keberuntungan saja. Padahal permainan Slot88 itu bukanlah permainan keberuntungan melainkan permainan skill yang pastinya membutuhkan strategi dan trik bermain agar anda bisa memperoleh kemenangan di dalam permainan itu.

Berbicara mengenai trik dan strategi yang bisa digunakan untuk bisa menang mudah di dalam permainan taruhan judi Slot88, tentu banyak hal yang bisa dilakukan. Disini kita akan coba pelajari beberapa hal yang meliputi trik dan strategi tersebut sebagai berikut:

1. Pelajari Aturan main

Langkah pertama yang perlu dan wajib Anda lakukan adalah mempelajari aturan main. Sebagaimana diketahui bahwa aturan main dari permainan taruhan judi Slot88 itu jadi suatu hal yang penting untuk dimengerti. Ada banyak simbol dari jenis permainan Slot88 yang anda mainkan yang harus Anda pahami terlebih dahulu sebelum Kemudian Anda memutuskan untuk terjun dalam permainan itu.

2. Memilih permainan Slot88 dengan RTP tinggi

Memilih permainan Slot88 yang memiliki tingkat kemenangan tinggi bisa menjadi suatu cara terbaik untuk memperoleh kemenangan mudah di dalam permainan itu. Maka dari itu …




mena

Monday Dec 10 - The Holy Martyrs Menas, Hermogenes and Eugraphus




mena

Dec 10 - Holy Martyrs Menas, Hermogenes And Eugraphus




mena

Dec 10 - Holy Martyrs Menas, Hermogenes And Eugraphus




mena

Dec 10 - Holy Martyrs Menas, Hermogenes And Eugraphus




mena

Holy Martyrs Menas, Hermogenes, and Eugraphus




mena

Holy Martyrs Menas, Hermogenes, and Eugraphus




mena

Nov 11 - Holy Martyr Menas




mena

Nov 11 - Holy Martyr Menas




mena

Holy Martyr Menas




mena

Jul 28 - Holy Apostles Of The Seventy And Deacons Prochorus, Nicanor, Timon And Parmenas




mena

Holy Apostles of the Seventy and Deacons Prochorus, Nicanor, Timon, and Parmenas




mena

Holy Martyr Menas




mena

Holy Martyrs Menas, Hermogenes, and Eugraphus




mena

Holy Apostles of the Seventy and Deacons Prochorus, Nicanor, Timon, and Parmenas




mena

Holy Martyr Menas




mena

Holy Martyrs Menas, Hermogenes and Eugraphus




mena

Holy Apostles of the Seventy and Deacons Prochorus, Nicanor, Timon, and Parmenas




mena

Holy Martyr Menas




mena

Holy Apostles of the Seventy and Deacons Prochorus, Nicanor, Timon and Parmenas




mena

Holy Apostles of the Seventy and Deacons Prochorus, Nicanor, Timon and Parmenas




mena

Holy Martyrs Menas, Hermogenes and Eugraphus




mena

Holy Apostles of the Seventy and Deacons Prochorus, Nicanor, Timon and Parmenas

They are mentioned by name in Acts 6:5. St Prochorus became Bishop of Nicomedia and reposed in peace. St Nicanor was stoned to death in Jerusalem. St Timon became Bishop of Bostra in Arabia and ended his life in martyrdom by fire at the hands of the pagans. St Parmenas died in peace in Jerusalem.




mena

Holy Martyr Menas (~304)

This holy Martyr was an Egyptian and a soldier during the reigns of Diocletian and Maximian. Though he was known for his valor in combat, he renounced his soldier's rank when his legion was ordered to seize Christians in north Africa. Fleeing to the mountains, he dwelt there for some time in silence and solitude, devoting his days to prayer. In time, he presented himself at a pagan festival, denounced the idols and declared himself a Christian. For this he was handed over to the governor of the city, who subjected him to horrible tortures and finally had him beheaded. Some faithful retrieved part of his relics and gave them honorable burial near Lake Mareotis, about thirty miles from Alexandria. The church built over his tomb became a place of pilgrimage not only for countless Egyptians but for Christians all over the world: evidence has been found of journeys to his shrine from as far away as Ireland.   The Synaxarion gives an account of the Saint's intervention in the Second World War: "In June 1942, during the North-Africa campaign that was decisive for the outcome of the Second World War, the German forces under the command of General Rommel were on their way to Alexandria, and happened to make a halt near a place which the Arabs call El-Alamein after Saint Menas. An ancient ruined church there was dedicated to the Saint; and there some people say he is buried. Here the weaker Allied forces including some Greeks confronted the numerically and militarily superior German army, and the result of the coming battle seemed certain. During the first night of engagement, Saint Menas appeared in the midst of the German camp at the head of a caravan of camels, exactly as he was shown on the walls of the ruined church in one of the frescoes depicting his miracles. This astounding and terrifying apparition so undermined German morale that it contributed to the brilliant victory of the Allies. The Church of Saint Menas was restored in thanksgiving and a small monastery was established there."




mena

Holy Martyrs Menas, Hermogenes and Eugraphus (235)

Menas was an Athenian, a courtier of the Emperor Maximinus, and a secret Christian. Once there was an outbreak of civil unrest in Alexandria, brought about by various political factions, and by the increasing success of Christian missionaries in turning the Alexandrian people from the idols. The Emperor sent Menas to reconcile the parties and settle the dispute. On his arrival, Menas quickly resolved the political troubles and restored peace to the city; but instead of putting down Christianity as the Emperor had desired, he did everything in his power to protect the Christians and encourage the spread of the Gospel. When word of this came to the Emperor, he sent another trusted courtier, Hermogenes, to re-establish Imperial authority and to execute Menas if he would not renounce Christ. Hermogenes followed these orders scrupulously: he subjected the godly Menas to various horrid tortures in the public arena. But Menas was miraculously preserved through them all, and when he finally appeared in the arena, flanked by two shining Angels, Hermogenes repented and confessed Christ. He in turn became such a fervent advocate for the Gospel that he was soon made a Bishop (!). Finally the Emperor decided that the only solution was to come to Alexandria himself. There he had both Menas and Hermogenes cruelly tortured to death in secret, lest they perform any public miracles; but when the Emperor presented himself before the people at the arena the following day, the two Saints, miraculously preserved, appeared there also, causing the people to cry out "Christ is the only true God!" At the sight, Menas' scribe Eugraphus declared himself a Christian, leaped into the arena and publicly demanded the honor of dying with them. All three were beheaded. Their precious relics were later taken to Constantinople, where they worked many miracles.




mena

Holy Martyr Menas (~304)

This holy Martyr was an Egyptian and a soldier during the reigns of Diocletian and Maximian. Though he was known for his valor in combat, he renounced his soldier's rank when his legion was ordered to seize Christians in north Africa. Fleeing to the mountains, he dwelt there for some time in silence and solitude, devoting his days to prayer. In time, he presented himself at a pagan festival, denounced the idols and declared himself a Christian. For this he was handed over to the governor of the city, who subjected him to horrible tortures and finally had him beheaded. Some faithful retrieved part of his relics and gave them honorable burial near Lake Mareotis, about thirty miles from Alexandria. The church built over his tomb became a place of pilgrimage not only for countless Egyptians but for Christians all over the world: evidence has been found of journeys to his shrine from as far away as Ireland.   The Synaxarion gives an account of the Saint's intervention in the Second World War: "In June 1942, during the North-Africa campaign that was decisive for the outcome of the Second World War, the German forces under the command of General Rommel were on their way to Alexandria, and happened to make a halt near a place which the Arabs call El-Alamein after Saint Menas. An ancient ruined church there was dedicated to the Saint; and there some people say he is buried. Here the weaker Allied forces including some Greeks confronted the numerically and militarily superior German army, and the result of the coming battle seemed certain. During the first night of engagement, Saint Menas appeared in the midst of the German camp at the head of a caravan of camels, exactly as he was shown on the walls of the ruined church in one of the frescoes depicting his miracles. This astounding and terrifying apparition so undermined German morale that it contributed to the brilliant victory of the Allies. The Church of Saint Menas was restored in thanksgiving and a small monastery was established there."




mena

Holy Martyrs Menas, Hermogenes and Eugraphus (235)

Menas was an Athenian, a courtier of the Emperor Maximinus, and a secret Christian. Once there was an outbreak of civil unrest in Alexandria, brought about by various political factions, and by the increasing success of Christian missionaries in turning the Alexandrian people from the idols. The Emperor sent Menas to reconcile the parties and settle the dispute. On his arrival, Menas quickly resolved the political troubles and restored peace to the city; but instead of putting down Christianity as the Emperor had desired, he did everything in his power to protect the Christians and encourage the spread of the Gospel. When word of this came to the Emperor, he sent another trusted courtier, Hermogenes, to re-establish Imperial authority and to execute Menas if he would not renounce Christ. Hermogenes followed these orders scrupulously: he subjected the godly Menas to various horrid tortures in the public arena. But Menas was miraculously preserved through them all, and when he finally appeared in the arena, flanked by two shining Angels, Hermogenes repented and confessed Christ. He in turn became such a fervent advocate for the Gospel that he was soon made a Bishop (!). Finally the Emperor decided that the only solution was to come to Alexandria himself. There he had both Menas and Hermogenes cruelly tortured to death in secret, lest they perform any public miracles; but when the Emperor presented himself before the people at the arena the following day, the two Saints, miraculously preserved, appeared there also, causing the people to cry out "Christ is the only true God!" At the sight, Menas' scribe Eugraphus declared himself a Christian, leaped into the arena and publicly demanded the honor of dying with them. All three were beheaded. Their precious relics were later taken to Constantinople, where they worked many miracles.




mena

Holy Martyr Menas (~304)

This holy Martyr was an Egyptian and a soldier during the reigns of Diocletian and Maximian. Though he was known for his valor in combat, he renounced his soldier's rank when his legion was ordered to seize Christians in north Africa. Fleeing to the mountains, he dwelt there for some time in silence and solitude, devoting his days to prayer. In time, he presented himself at a pagan festival, denounced the idols and declared himself a Christian. For this he was handed over to the governor of the city, who subjected him to horrible tortures and finally had him beheaded. Some faithful retrieved part of his relics and gave them honorable burial near Lake Mareotis, about thirty miles from Alexandria. The church built over his tomb became a place of pilgrimage not only for countless Egyptians but for Christians all over the world: evidence has been found of journeys to his shrine from as far away as Ireland.   The Synaxarion gives an account of the Saint's intervention in the Second World War: "In June 1942, during the North-Africa campaign that was decisive for the outcome of the Second World War, the German forces under the command of General Rommel were on their way to Alexandria, and happened to make a halt near a place which the Arabs call El-Alamein after Saint Menas. An ancient ruined church there was dedicated to the Saint; and there some people say he is buried. Here the weaker Allied forces including some Greeks confronted the numerically and militarily superior German army, and the result of the coming battle seemed certain. During the first night of engagement, Saint Menas appeared in the midst of the German camp at the head of a caravan of camels, exactly as he was shown on the walls of the ruined church in one of the frescoes depicting his miracles. This astounding and terrifying apparition so undermined German morale that it contributed to the brilliant victory of the Allies. The Church of Saint Menas was restored in thanksgiving and a small monastery was established there."




mena

Holy Martyrs Menas, Hermogenes and Eugraphus (235)

Menas was an Athenian, a courtier of the Emperor Maximinus, and a secret Christian. Once there was an outbreak of civil unrest in Alexandria, brought about by various political factions, and by the increasing success of Christian missionaries in turning the Alexandrian people from the idols. The Emperor sent Menas to reconcile the parties and settle the dispute. On his arrival, Menas quickly resolved the political troubles and restored peace to the city; but instead of putting down Christianity as the Emperor had desired, he did everything in his power to protect the Christians and encourage the spread of the Gospel. When word of this came to the Emperor, he sent another trusted courtier, Hermogenes, to re-establish Imperial authority and to execute Menas if he would not renounce Christ. Hermogenes followed these orders scrupulously: he subjected the godly Menas to various horrid tortures in the public arena. But Menas was miraculously preserved through them all, and when he finally appeared in the arena, flanked by two shining Angels, Hermogenes repented and confessed Christ. He in turn became such a fervent advocate for the Gospel that he was soon made a Bishop (!). Finally the Emperor decided that the only solution was to come to Alexandria himself. There he had both Menas and Hermogenes cruelly tortured to death in secret, lest they perform any public miracles; but when the Emperor presented himself before the people at the arena the following day, the two Saints, miraculously preserved, appeared there also, causing the people to cry out "Christ is the only true God!" At the sight, Menas' scribe Eugraphus declared himself a Christian, leaped into the arena and publicly demanded the honor of dying with them. All three were beheaded. Their precious relics were later taken to Constantinople, where they worked many miracles.




mena

Holy Martyr Menas (~304) - November 11th

This holy Martyr was an Egyptian and a soldier during the reigns of Diocletian and Maximian. Though he was known for his valor in combat, he renounced his soldier's rank when his legion was ordered to seize Christians in north Africa. Fleeing to the mountains, he dwelt there for some time in silence and solitude, devoting his days to prayer. In time, he presented himself at a pagan festival, denounced the idols and declared himself a Christian. For this he was handed over to the governor of the city, who subjected him to horrible tortures and finally had him beheaded. Some faithful retrieved part of his relics and gave them honorable burial near Lake Mareotis, about thirty miles from Alexandria. The church built over his tomb became a place of pilgrimage not only for countless Egyptians but for Christians all over the world: evidence has been found of journeys to his shrine from as far away as Ireland.   The Synaxarion gives an account of the Saint's intervention in the Second World War: "In June 1942, during the North-Africa campaign that was decisive for the outcome of the Second World War, the German forces under the command of General Rommel were on their way to Alexandria, and happened to make a halt near a place which the Arabs call El-Alamein after Saint Menas. An ancient ruined church there was dedicated to the Saint; and there some people say he is buried. Here the weaker Allied forces including some Greeks confronted the numerically and militarily superior German army, and the result of the coming battle seemed certain. During the first night of engagement, Saint Menas appeared in the midst of the German camp at the head of a caravan of camels, exactly as he was shown on the walls of the ruined church in one of the frescoes depicting his miracles. This astounding and terrifying apparition so undermined German morale that it contributed to the brilliant victory of the Allies. The Church of Saint Menas was restored in thanksgiving and a small monastery was established there."




mena

Holy Martyrs Menas, Hermogenes and Eugraphus (235) - December 10th

Menas was an Athenian, a courtier of the Emperor Maximinus, and a secret Christian. Once there was an outbreak of civil unrest in Alexandria, brought about by various political factions, and by the increasing success of Christian missionaries in turning the Alexandrian people from the idols. The Emperor sent Menas to reconcile the parties and settle the dispute. On his arrival, Menas quickly resolved the political troubles and restored peace to the city; but instead of putting down Christianity as the Emperor had desired, he did everything in his power to protect the Christians and encourage the spread of the Gospel. When word of this came to the Emperor, he sent another trusted courtier, Hermogenes, to re-establish Imperial authority and to execute Menas if he would not renounce Christ. Hermogenes followed these orders scrupulously: he subjected the godly Menas to various horrid tortures in the public arena. But Menas was miraculously preserved through them all, and when he finally appeared in the arena, flanked by two shining Angels, Hermogenes repented and confessed Christ. He in turn became such a fervent advocate for the Gospel that he was soon made a Bishop (!). Finally the Emperor decided that the only solution was to come to Alexandria himself. There he had both Menas and Hermogenes cruelly tortured to death in secret, lest they perform any public miracles; but when the Emperor presented himself before the people at the arena the following day, the two Saints, miraculously preserved, appeared there also, causing the people to cry out "Christ is the only true God!" At the sight, Menas' scribe Eugraphus declared himself a Christian, leaped into the arena and publicly demanded the honor of dying with them. All three were beheaded. Their precious relics were later taken to Constantinople, where they worked many miracles.




mena

Holy Martyr Menas (~304)

This holy Martyr was an Egyptian and a soldier during the reigns of Diocletian and Maximian. Though he was known for his valor in combat, he renounced his soldier's rank when his legion was ordered to seize Christians in north Africa. Fleeing to the mountains, he dwelt there for some time in silence and solitude, devoting his days to prayer. In time, he presented himself at a pagan festival, denounced the idols and declared himself a Christian. For this he was handed over to the governor of the city, who subjected him to horrible tortures and finally had him beheaded. Some faithful retrieved part of his relics and gave them honorable burial near Lake Mareotis, about thirty miles from Alexandria. The church built over his tomb became a place of pilgrimage not only for countless Egyptians but for Christians all over the world: evidence has been found of journeys to his shrine from as far away as Ireland.   The Synaxarion gives an account of the Saint's intervention in the Second World War: "In June 1942, during the North-Africa campaign that was decisive for the outcome of the Second World War, the German forces under the command of General Rommel were on their way to Alexandria, and happened to make a halt near a place which the Arabs call El-Alamein after Saint Menas. An ancient ruined church there was dedicated to the Saint; and there some people say he is buried. Here the weaker Allied forces including some Greeks confronted the numerically and militarily superior German army, and the result of the coming battle seemed certain. During the first night of engagement, Saint Menas appeared in the midst of the German camp at the head of a caravan of camels, exactly as he was shown on the walls of the ruined church in one of the frescoes depicting his miracles. This astounding and terrifying apparition so undermined German morale that it contributed to the brilliant victory of the Allies. The Church of Saint Menas was restored in thanksgiving and a small monastery was established there."




mena

Holy Martyrs Menas, Hermogenes and Eugraphus (235)




mena

Holy Martyr Menas (~304)

This holy Martyr was an Egyptian and a soldier during the reigns of Diocletian and Maximian. Though he was known for his valor in combat, he renounced his soldier's rank when his legion was ordered to seize Christians in north Africa. Fleeing to the mountains, he dwelt there for some time in silence and solitude, devoting his days to prayer. In time, he presented himself at a pagan festival, denounced the idols and declared himself a Christian. For this he was handed over to the governor of the city, who subjected him to horrible tortures and finally had him beheaded. Some faithful retrieved part of his relics and gave them honorable burial near Lake Mareotis, about thirty miles from Alexandria. The church built over his tomb became a place of pilgrimage not only for countless Egyptians but for Christians all over the world: evidence has been found of journeys to his shrine from as far away as Ireland.   The Synaxarion gives an account of the Saint's intervention in the Second World War: "In June 1942, during the North-Africa campaign that was decisive for the outcome of the Second World War, the German forces under the command of General Rommel were on their way to Alexandria, and happened to make a halt near a place which the Arabs call El-Alamein after Saint Menas. An ancient ruined church there was dedicated to the Saint; and there some people say he is buried. Here the weaker Allied forces including some Greeks confronted the numerically and militarily superior German army, and the result of the coming battle seemed certain. During the first night of engagement, Saint Menas appeared in the midst of the German camp at the head of a caravan of camels, exactly as he was shown on the walls of the ruined church in one of the frescoes depicting his miracles. This astounding and terrifying apparition so undermined German morale that it contributed to the brilliant victory of the Allies. The Church of Saint Menas was restored in thanksgiving and a small monastery was established there."




mena

Theologoumena

Fr. Ted responds to questions he has received regarding the moments immediately following death. He explains that all answers fall into the category of opinion. Our focus instead should be on living our Christian lives here on earth.




mena

Netanyahu s’est entretenu 3 fois avec Trump depuis sa réélection à propos de la "menace iranienne"

Netanyahu s’est entretenu 3 fois avec Trump depuis sa réélection à propos de la "menace iranienne"




mena

Methodological Approaches for Researching Complex Organizational Phenomena




mena

Qur'anic Evidences for the Motion of the Sun and the Phenomena of Night and Day




mena

Linking solid-state phenomena via energy differences in `archetype crystal structures'

Categorization underlies understanding. Conceptualizing solid-state structures of organic molecules with `archetype crystal structures' bridges established categories of disorder, polymorphism and solid solutions and is herein extended to special position and high-Z' structures. The concept was developed in the context of disorder modelling [Dittrich, B. (2021). IUCrJ, 8, 305–318] and relies on adding quantum chemical energy differences between disorder components to other criteria as an explanation as to why disorder – and disappearing disorder – occurs in an average structure. Part of the concept is that disorder, as probed by diffraction, affects entire molecules, rather than just the parts of a molecule with differing conformations, and the finding that an R·T energy difference between disorder archetypes is usually not exceeded. An illustrative example combining disorder and special positions is the crystal structure of oestradiol hemihydrate analysed here, where its space-group/subgroup relationship is required to explain its disorder of hydrogen-bonded hydrogen atoms. In addition, we show how high-Z' structures can also be analysed energetically and understood via archetypes: high-Z' structures occur when an energy gain from combining different rather than overall alike conformations in a crystal significantly exceeds R·T, and this finding is discussed in the context of earlier explanations in the literature. Twinning is not related to archetype structures since it involves macroscopic domains of the same crystal structure. Archetype crystal structures are distinguished from crystal structure prediction trial structures in that an experimental reference structure is required for them. Categorization into archetype structures also has practical relevance, leading to a new practice of disorder modelling in experimental least-squares refinement alluded to in the above-mentioned publication.




mena

Mastercard joins Buna to boost MENA payments

Mastercard has joined



mena

A New Sports Apparel Brand for Sneakerheads called Sneakerhabbit is a must-have and the Hoodies are Phenomenal

We were born from the need to create a quality apparel brand whose designs scream a love for sneakers, and whose collections are the completion of every sneakerhead's wardrobe.